Published for the Division of Materials Sciences, Office of Basic Energy Sciences, USDOE, under Contract W-7405-eng-82 with the Ames Laboratory, Iowa State University. Funded by DMS/BES/USDOE, ARPA, ONR, NSF, EPRI, and other agencies, organizations, and individuals.
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PLEASE NOTE: Issues of High-Tc Update from November 15, 1993, onward are also available in coded Word versions (BINHEX and RTF). (These versions preserve the Greek letters, special characters, accents, etc.) If you are interested in the alternate formats, contact the editor for information.
PLEASE READ: The electronic-mail version of High-Tc Update is generated from a Macintosh Microsoft Word file and turned into a text file that can be transferred electronically. Formatting commands, Greek symbols, diacritical marks, etc. are lost in this transformation. In order to improve the readability of the e-mail version, the newsletter staff add explanatory marks as needed to the text file. For example, a carat (10^5) indicates a superscript (ten to the fifth). A carat followed by a bracket (cm^[-2]) indicates everything within the brackets is superscripted (centimeter to the minus 2). A bracket followed by a carat ([18]^O) indicates everything before the carat is superscripted. An underline (M_i) indicates a subscript (M subscript i). Most Greek letters are spelled out (Delta, mu, tau, pi, Omega), although delta is left as "d." In most instances, easily recognizable formulas or units are left as they appear: Tc, Jc, YBa2Cu3O7, O2. Mu-m is changed to micrometers. Diacritical marks (accents, tildes, carats, etc.) are removed, but the German umlaut (e.g., a, o, or u with two dots over it) is changed into a, o, or u followed by e. If needed for clarity, hyphens are occasionally inserted between spelled-out Greek letters or symbols (ohm-cm, sin-theta).
NOTA BENE:
126 K in Ba-Ca-Cu-O
A preprint by C. W. Chu et al. (TCSUH) reports the detection of a reproducible bulk superconducting transition in the Ba-Ca-Cu-O system at 126 K under ambient pressure, the highest transition temperature in a compound system not containing volatile toxic elements such as Tl or Hg. Both resistive and magnetic-susceptibility measurements showed sharp transitions to the superconducting state in a sample with up to 25% of the volume fraction in the 126 K phase. In other samples, the authors also detected two distinct transitions at ~105 K and 90 K. The samples were prepared by high-pressure synthesis from precursors with various nominal compositions such as CuBa2Can-1CunOx [Cu-12(n-1)n] with n = 3 or 4 and Ba2Can-1CunOx [2(n-1)n] with n = 3 or 4. The authors found that the formation conditions and the phase-stability region for the 126 K phase are very different from those of Cu-12(n-1)n. In spite of the large volume fraction of the 126 K phase, the x-ray-diffraction patterns of the samples were of poor quality, preventing the authors from determining the structures of the new phases, except that the data showed no presence of Cu-12(n-1)n. The authors conclude that the high- temperature-superconducting phases belong to a new compound family that may be expressed as Ba2Can-1CunOx [2(n-1)n].
Pseudogap
As noted in a preprint by V. J. Emery (Brookhaven) et al., when holes are doped into an antiferromagnetic insulator, they form a slowly fluctuating array of topological defects (metallic stripes), in which the motion of the holes exhibits a self-organized quasi-one-dimensional behavior. The accompanying lateral confinement of the intervening Mott- insulating regions induces a spin gap or pseudogap in the environment of the stripes. The authors present a theory of underdoped high- temperature superconductors and show that there is a local separation of spin and charge, and that the mobile holes on an individual stripe acquire a spin gap via pair hopping between the stripe and its environment, i.e., via a magnetic analog of the usual superconducting proximity effect. In this way a high pairing scale without a large mass renormalization is established, despite the strong Coulomb repulsion between the holes. Thus the mechanism of pairing is the generation of a spin gap in spatially confined Mott-insulating regions of the material in the proximity of the metallic strips. At nonvanishing stripe densities, Josephson coupling between stripes produces a dimensional crossover to a state with long-range superconducting phase coherence. The authors establish this picture by obtaining exact and well- controlled approximate solutions of a model of a one-dimensional electron gas in an active environment. The authors also give an extended discussion of the experimental evidence supporting the relevance of these results to the cuprate superconductors.
A preprint by A. Kallio (Oulu) et al. proposes a treatment of the boson- fermion equilibrium reaction B^[2+] = 2h^+ suitable for understanding the normal states of underdoped superconductors such as YBa2Cu3O7-d, where the bosons may continue to exist as preformed pairs for T > Tc and gradually decay into pairing holes. The densities of bosons and fermions, given by a function f(T), are temperature dependent. A treatment in analogy with ionization using the grand potential Omega(T,V,mu) leads to a reduction of the free-boson contribution to the entropy and specific heat near Tc. A large free-boson contribution immediately above Tc, not seen in experiments, has been the main argument against the boson models. The authors' treatment explains the Hall-coefficient scaling law observed experimentally by H. W. Hwang et al. [Phys. Rev. Lett. 72, 2636 (1994)] in La2-xSrxCuO4. The logarithmic behavior of resistivities rho_[ab] and rho_c in strong magnetic fields observed by Y. Ando et al. [Phys. Rev. Lett. 75, 4662 (1995)] can come from bosons that are 3D rather than 2D in character. The authors propose that to create superconductors with maximal Tc, one should make the boson delocalization temperature T_[BL](>Tc) high.
Using angle-resolved photoemission spectroscopy, H. Ding (Illinois- Chicago and Argonne) et al. have found that underdoped Bi2Sr2CaCu2O8+d (Bi-2212) appears to have a large Fermi surface centered at (pi,pi), even for samples with Tc as low as 15 K. No clear evidence of a Fermi surface pocket around (pi/2,pi/2) has been found. These conclusions are based on a determination in the pseudogap regime Tc < T < T* of the minimum gap locus, which is found to coincide with the locus of gapless excitations in momentum space (Fermi surface) determined above T*. The authors argue that the pseudogap is more likely of precursor-pairing origin than of magnetic origin.
Optical reflectivity measurements by R. Hauff et al. (SRL-ISTEC) with E||c on YBa2(Cu1-xZnx)3O6.6 reveal a dramatic Zn-substitution effect on the anomaly of the in-plane oxygen bending mode and the broad absorption band around 450 cm^[-1] observed at low temperatures for x = 0, while the low-omega suppression of the optical conductivity remains unchanged. The authors note that this indicates a close relationship between the phonon anomaly and the absorption band, and that the conductivity suppression is an independent phenomenon. The former suggests a coupling of phonons to spin fluctuations at (pi,pi), leading to anomalous spectral behavior when a spin gap opens.
d-Wave Probes
Pure electronic Raman spectra with no phonon structures superimposed upon the electronic continuum are reported by A. Sacuto (Paris) et al. in optimally doped HgBa2CaCu2O6+d [Hg-1212] single crystals with Tc = 126 K. The spectra with A_[1g], B_[1g], and B_[2g] symmetries, including the crucial low-energy frequency dependence of the electronic scattering, were directly measured. Both the B_[2g] and the B_[1g] spectra were found to exhibit a strong intrinsic linear term, suggesting that the nodes of the superconducting energy gap are shifted away from the [110] and [110] directions, a result inconsistent with a pure d_[x^2-y^2] model.
The Ginzburg-Landau equations have been derived microscopically by K. Maki (USC) and M. T. Beal-Monod (Orsay) from their d+s-wave model of superconductivity in high-Tc cuprates with an orthorhombic distortion. The authors include the effect of a-b anisotropy in the normal state. When the applied magnetic field B is in the ab plane, the authors find an expression for the upper critical field H_[c2], which is a function of cos2-theta, where theta is the angle between B and the a axis. For YBa2Cu3O7-d, the authors predict H_[c2]^b/H_[c2]^a = 3.15, although this is much larger than this ratio reported in a recent experiment.
Using the Bogoliubov-de Gennes equation, Y. Morita (Tokyo) et al. have studied the quasiparticle spectrum around a single vortex in a d-wave superconductor when the magnetic field is parallel to the c axis. In the temperature region where the Ginzburg-Landau equation is valid, the authors find that the local density of states preserves a circular symmetry when the symmetry of the superconducting order parameter is pure d-wave. However, it exhibits four-fold symmetry when mixing of an s-wave component occurs. A peak with a large energy gap is found in the local density of states at the center of the vortex, which corresponds to the lowest bound state. The results are consistent with a recent scanning-tunneling-microscope (STM) experiment in an YBa2Cu3O7-d (YBCO) single crystal. The authors also discuss the breakdown of the Eilenberger theory in YBCO and in high-Tc superconductors in general.
Two preprints by O. M. Froehlich (Tuebingen) et al. report high- precision measurements of the magnetic-field dependence of the in-plane penetration depth lambda_[ab](T) in YBa2Cu3O7-d (YBCO) and La1.85Sr0.15CuO4-d (LSCO) thin films. The technique, based on measurements of the critical current of bicrystal grain-boundary junctions, has a resolution better than 0.2 Angstrom. The data for Delta-lambda_[ab](T) = lambda_[ab](T) - lambda_[ab](0) in both YBCO and LSCO confirm with high accuracy the temperature dependence expected for d_[x^2-y^2] symmetry of the superconducting order parameter.
RBa2Cu3O7-d
The optical conductivity spectra of YBa2Cu3O7-d crystals have been investigated by S. Tajima et al. (SRL-ISTEC) using polarization E||c over a wide doping range from the heavily underdoped to the overdoped regime and focusing on the charge dynamics in the c direction. The authors obtain evidence for an electronic state characterized by carrier confinement in both the normal and superconducting states.
Resistive transitions in YBa2Cu3O7-d as a function of the angle and magnitude of the magnetic field (up to 12 T) are reported by S. Sarti et al. (Rome). The authors find that angular scaling of the resistance occurs for all angles in the upper part of the transition down to a field-dependent temperature T_f(H). The Landau-eigenfunction fluctuation theory of R. Ikeda et al. [J. Phys. Soc. Jpn. 60,1051 (1991)] fully explains the experimental findings for T > T_f, including the angular scaling and temperature dependence of the resistivity.
Large crystals (up to 3.5 mm x 4.5 mm x 60 mm) of NdBa2Cu3O7-d have been grown by K. Kuroda et al. (SRL-ISTEC) using the traveling-solvent floating-zone method. The crystals showed superconducting properties throughout the crystal length with onset Tc = 94 K and Delta-Tc ~~ 5 K.
Bi Cuprates
A preprint by X. L. Wang et al. (Wollongong) reports the growth of Bi2Sr2CaCu2O8+d (Bi-2212) crystals by a spiral growth mechanism at a KCl flux surface. The authors found that all the growth spirals were square, with single and multiple spirals generated together, when the growth temperature was below 850^oC. The square shape of the growth spirals is attributed to (110) growth twins.
A detailed study of the melting equilibria of the Bi-Sr-Ca-Cu-O system in air is reported by W. Wong-Ng et al. (NIST-Gaithersburg). The authors determined the primary crystallization field of the 2212 phase and the effect of Ag addition. The 2212 phase was found to be in equilibrium with 10 other phases at 830^oC, resulting in at least 16 stable four-phase compatibility volumes. The authors note that their results impact on melt processing, crystal growth, and solidification, and thus should be considered in designing processing paths.
The melting of Bi2Sr2CaCu2O8+d (Bi-2212) has been studied by Th. Lang et al. (ETH-Zurich) under controlled oxygen partial pressures. Without Ag additions, the authors find that the solidus temperature T_[solidus] of Bi-2212 is decreased from 893^oC to 880^oC when the oxygen partial pressure is changed from P(O2) = 1 atm to 0.21 atm, and to 834^oC at 0.001 atm. With Ag additions exceeding 2 wt%, T_[solidus] is 868^oC at P(O2) = 1 atm, 860^oC at 0.21 atm, and 825^oC at 0.001 atm.
A preprint by H.-R. Wenk (UC-Berkeley and Grenoble) et al. reports the crystallographic texture of silver-sheathed monocore tapes and wires, and multifilamentary tapes containing Bi2Sr2CaCu2O8+d (Bi-2212) and Bi2Sr2Ca2Cu3O10+d (Bi-2223), using neutron diffraction. The multifilamentary tapes were found to have the highest degree of crystallite alignment.
The evolution of the transport critical current density Jc and irreversibility field H* as a function of heat treatment and pressing pressure during processing of Ag-sheathed (Bi,Pb)2Sr2Ca2Cu3O10+d [(Bi,Pb)-2223] tapes has been studied by H. S. Edelman et al. (Wisconsin-Madison). The authors measured the electric-field vs. current-density characteristics of bare cores of monofilament [(Bi,Pb)- 2223] tapes at 77 K at different stages of tape processing. The data are consistent with an improvement in Jc from two factors: (a) an increase in the 2223 phase fraction with increasing heat treatment and (b) an increase in the flux-pinning properties of the composite. The experiments show that improving Jc involves control of at least three factors: enhancing the volume fraction of the 2223 phase, increasing flux pinning, and enhancing the connectivity of the grain boundaries along the current path.
Hg Cuprates
Double-(Hg,Tl)-O-layer superconductors with three or four CuO2 sheets, (Hg1-xTlx)2Ba2Can-1CunOy [(Hg,Tl)-22(n-1)n] (x = 0.3-0.6, n = 3 and 4) have been synthesized under high pressure and high temperature by T. Tatsuki et al. (SRL-ISTEC). The Tc of as-sintered (Hg,Tl)-2223 increased from 45 K to 81 K as x increased from 0.3 to 0.6, and Ar annealing raised Tc in the latter sample to ~90 K, indicating that as- synthesized 2223 phases are highly overdoped. The Tc (~115 K) of (Hg,Tl)-2234, on the other hand, was found to be nearly independent of Tl content and Ar annealing, suggesting that as-synthesized 2234 samples are nearly optimally doped.
A method of high-pressure synthesis of HgBa2Ca2Cu3O8+d (Hg-1223) without a precursor has been developed by Y. Moriwaki et al. (SRL-ISTEC). The method allows the synthesis of nearly single-phase Hg-1223 through a single-step process.
Superconducting HgBa2CuO4+d (Hg-1201) samples containing Agx additions with molar fraction up to x = 0.5 have been studied by J. R. Thompson (Oak Ridge and Tennessee) et al. The Ag additions led to changes in the superconducting properties, which can be interpreted in terms of the hole density, obtained from the London penetration depth lambda measured in the same materials. The irreversible magnetic properties are well described in terms of thermally activated tunneling of pancake vortices through a surface barrier.
Other Cuprates
The distribution of oxygen in single crystals of La2CuO4+d with d = 0.03 and d = 0.04 in the temperature region 10 K <= T <= 293 K has been studied by A. M. Balagurov (Dubna) et al. using a high-resolution neutron diffractometer. While the oxygen distribution remained homogeneous in La2CuO4.03, phase separation into oxygen-rich and oxygen- poor regions (both with the same space symmetry) occurred in La2CuO4.04.
A preprint by S. Yomo (Hokkaido Tokai) et al. reports measurements of the superconducting transition temperature Tc and the Hall coefficient R_H at 77 K under pressure up to 1.2 GPa in La2CuO4+d (d = 0.035-0.072), the pressure being applied at room temperature. The R_H was found to be positive and to decrease with increasing d, which indicates increasing hole carriers with d, but also was found to be very insensitive to pressure. The Tc of the 32 K phase, however, showed a large positive pressure effect of 9-17 K/GPa, which cannot be explained by a simple charge-transfer model.
New cuprate superconductors containing phosphate groups, (Cu0.5P0.5)Sr2(Ca,Y)n-1CunOy (n = 3-6), have been synthesized by M. Isobe et al. (NIRIM) under high pressures of 5-6 GPa. They show superconductivity with Tc = 64-80 K for n = 3, 70-112 K for n = 4, and ~80 K for n = 5 and 6, depending on the Y and O contents.
ErNi2B2C
Using small-angle neutron scattering (SANS) and magnetic decoration, M. R. Eskildsen (Riso) et al. have observed a topological transition in the vortex-line lattice in ErNi2B2C. The high-field square lattice slowly transforms into a hexagonal lattice as the field is reduced below about 500 Oe. The square lattice is aligned with the [110] direction of the tetragonal crystal, while the two domains of the hexagonal lattice are aligned along the [100] and [010] directions. The transformation proceeds via an area-preserving rhombohedral distortion along the [100] axis. The structural transition also affects the rf kinetic inductance, reflecting differences in the pinning for the two vortex-lattice topologies.
Vortices
Simultaneous measurements of dc resistivity and local magnetization (using a 2D-electron-gas-based Hall-probe array) in a crystal of Bi2Sr2CaCu2O8+d (Bi-2212) are reported by T. Tsuboi et al. (Tokyo). The resistivity in the vortex-liquid phase was found to be nonlinear near the vortex-lattice-melting transition and TAFF-like at higher fields, demonstrating that pinning is relevant even in the vortex liquid. The authors carry out a quantitative analysis, which shows that the vortex liquid at higher fields is highly viscous. In the nonlinear region, a current-dependent hump was observed in the field dependence of the resistivity, which may result from current-induced vortex cutting.
According to a preprint by C. Timm (Hamburg), spontaneously created vortex-antivortex pairs are the predominant source of flux noise in high-temperature superconductors in the absence of an applied magnetic field. The author calculates the flux-noise power spectrum for the highly anisotropic high-temperature superconductor Bi2Sr2CaCu2O8+d (Bi- 2212), both for bulk crystals and ultrathin films. The author finds white noise at low frequencies omega and a spectrum proportional to 1/omega^[3/2] at high frequencies.
A preprint by S. G. Doettinger et al. (Tuebingen) discusses experimental evidence (from microwave power absorption and from electrical resistance at high vortex velocities) for the Kramer-Pesch effect, in which the vortex-core radius in a type-II superconductor decreases with decreasing temperature as xi proportional toT.
Thin Films
HgBa2Ca2Cu3O8+d (Hg-1223) films with a thickness of 1-2 micrometers have been grown epitaxially on SrTiO3 by Y. Moriwaki et al. (SRL-ISTEC) using a spray pyrolysis technique. The as-fabricated films exhibited a Tc(zero-resistance) = 123 K and a critical current density Jc(77K,0T) = 3.7 x 10^5 A/cm^2, but additional post-annealing at 320^oC for 50 h in flowing oxygen improved the transport properties to Tc(zero-resistance) ~~ 130 K and Jc(77K,0T) ~~ 4.4 x 10^5 A/cm^2.
Measurements of quasiparticle tunneling (QPT) in grain-boundary Josephson junctions are reported in two preprints by O. M. Froehlich (Tuebingen) et al. and one by P. Richter (Tuebingen) et al. In the low- voltage regime the authors observed a zero-bias conductance peak, which they discuss in terms of spin-flip and Kondo-type scattering at the interface using the Anderson-Appelbaum model.
The interaction of microwaves (30-55 GHz) with a single high-Tc superconducting YBa2Cu3O7-d (YBCO) bi-epitaxial grain-boundary junction and with an array of two junctions connected in series has been investigated experimentally by K. Y. Constantinian (Moscow) et al. at temperatures 4.2-77 K and in magnetic fields -0.4 mT to +0.4 mT. The experimental results were used as input data for computer simulations, which confirmed the hypothesis that the current through a grain-boundary junction is transported by a parallel array of lumped Josephson junctions.
Applications
A preprint by H. Fuke et al. (SRL-ISTEC) reports the fabrication of coplanar-type dc SQUIDs using NdBa2Cu3O7-d superconducting thin films. The authors also operated fundamental single-flux-quantum (SFQ) circuits. The Josephson junctions were made by the narrow-focused ion- beam-irradiation technique. For a 145 micrometer-wide and 10 micrometer-long logic SQUID with a critical current of 105 microamperes and an inductive parameter beta_L of 28, a store and a restore of the flux quantum were demonstrated at temperatures of 4.2-30 K. These operations were performed with an input pulse width of 5 ns, the shortest input pulse width available from the authors' function- generating equipment. The results show the possibility of high-speed operation in all-high-Tc superconducting digital circuits.
An AND/OR logic device, consisting of rf and dc SQUIDs, has been demonstrated in a related preprint by K. Saitoh et al. (SRL-ISTEC). The logic operation is based on the nonlinear characteristics of the internal and external magnetic flux in the rf SQUID, while the results of the logic operation are read out by the dc SQUID. The device was made of a NdBa2Cu3O7-d superconducting thin film with weak links fabricated using a narrow-focused Ga-ion-beam technology.
A preprint by E. Dantsker et al. (UC-Berkeley and LBNL) reports the reduction of 1/f noise in narrow-line-width high-temperature- superconducting dc SQUIDs cooled in an ambient magnetic field B_0. For B_0 less than a threshold value (about 33 microTesla in the best case), the low-frequency spectral density S_[phi](f) was independent of B_0, while for B_0 above this threshold, the noise increased rapidly because of vortex entry into the film. For large square-washer SQUIDs, S_[phi](f) scaled linearly with B_0.
Results of free spin-down in vacuum are reported by J. R. Hull et al. (Argonne) for an Evershed-type superconducting bearing, in which a permanent magnet (PM) ring is levitated over an array of high- temperature superconductors (HTSs) and under a similar PM ring in magnetic attraction. The velocity dependence of the rotational loss strongly suggests that the observed velocity-dependent losses are due primarily to eddy currents induced in the PM by inhomogeneity of the field produced by the magnetized HTS array. Significant levitation heights (>20 mm) are possible with this kind of bearing.
Theory
A preprint by J.J.M. Pothuizen (Groningen) et al. presents a theoretical k-dependent study of the single-hole states in Sr2CuO2Cl2. The authors demonstrate that the controversial 1-eV peaks in the high-Tc superconductors are quasiparticles derived from the same O 2p states as the Zhang-Rice singlets, but of different symmetry, and are intense in those regions of the Brillouin zone where the hybridization with the correlated Cu 3d states vanishes by symmetry. The authors then estimate the quasiparticle weight of the Zhang-Rice singlets, discuss the quasiparticle lineshape, and suggest a strong k dependence of the self- energy.
A related paper by R. Eder (Groningen) et al. reports an exact diagonalization study of the single-particle spectral function in the t- t'-t"-J model in 2D. The authors find that hole doping leads to a major reconstruction of the quasiparticle band structure near (pi,0). Whereas for the undoped system the quasiparticle states near (pi,0) are deep below the top of the band near (pi/2,pi/2), hole doping shifts these states up to E_F, resulting in extended flat-band regions close to E_F and around (pi,0).
The single-hole energy spectrum has been calculated by L. P. Gor'kov (Florida State and Landau Institute) and P. Kumar (Florida) using a three-band model in a mean-field approximation. The model assumes that the only relevant copper configurations are (d^9)Cu^[2+] and (d^[10])Cu^[1+]. To obtain a hole band consistent with the recent ARPES study in Sr2CuO2Cl2 by B. O. Wells et al. [Phys. Rev. Lett. 74, 964 (1995)], the authors found it necessary to account for the direct O-O overlap with a specific choice for the sign of the matrix element.
The consequences of hole doping on the superconducting cuprates in a theoretical model incorporating the van Hove scenario have been worked out by J. Bouvier and J. Bok (Paris). The authors find that the gap anisotropy Delta_[max]/Delta_[min] decreases with doping, in agreement with photoemission experiments.
A preprint by V. Z. Kresin (LBL) et al. theoretically considers a number of factors that can affect the isotope-effect coefficient alpha: magnetic scattering, the presence of a normal film (proximity effect), and nonadiabaticity (dynamic Jahn-Teller effect). The authors find results in good agreement with existing experimental data for the oxygen isotope effect in YBa2Cu3O7-d.
Overviews
A preprint by S. X. Dou et al. (Wollongong) reviews a number of techniques by which effective pinning centers can be introduced to improve flux pinning in Bi-(Pb)-Sr-Ca-Cu-O high-temperature superconductors. Pinning enhancements are caused by surface pinning through spiral growth structures, fine precipitates produced through phase transformations or phase-formation decomposition, inclusions through chemical doping or addition, defect cascades or columnar defects created by fast-neutron and heavy-ion-beam irradiation, and various defects induced by mechanical deformation (122 refs.).
The key issues regarding the physics and technology of high-temperature- superconducting (HTS) Josephson junctions are summarized, and possible routes to a useful HTS junction technology are discussed in a paper by R. Gross et al. (Koeln). The authors also discuss the effects of d_[x^2-y^2]-wave symmetry of the order parameter on HTS Josephson junctions (87 refs.).
Contributed by John R. Clem
Contents: Preprints begin on page 6; Coming Events begin on page 13; and FYI is on page 15.
High-Tc Update is available without charge to interested persons. Recipients are expected to participate in this information exchange by sending us preprints, reprints, meeting news, research news, etc. Contributions to defray the cost of newsletter printing and mailing are welcome.
PREPRINTS To obtain a particular preprint, contact the first author at the address given at the end of the citation. Help us expand this list by sending us your complete preprint. Please specify where and when your paper was submitted. An * next to an entry indicates it is a correction or revision of a previous entry. PACS codes and/or key words are given at the end of the citation.
B. A. Albiss, H. OEzkan, H. Boecuek, N. M. Gasanly, and I. Ercan, "Effect of Gamma Irradiation on Structure and Electrical Properties of (Bi,Pb)2Sr2Ca2Cu3O10 Superconductor." Presented at the 5th World Congress on Superconductivity, Budapest, Hungary, July 7 - 11, 1996; to be published in Superlatt. and Microstruc. Department of Physics, Middle East Technical University, 06531 Ankara, TURKEY; I. Ercan's telefax +90 312 8154307.
A. A. Aligia and J. M. Eroles, "Neutron-Diffraction Pattern Observed in YBa2Cu3O6.35: No Better Explanation than Oxygen Ordering." To be published in Physica C (in press). Centro Atomico Bariloche and Instituto Balseiro, Comision Nacional de Energia Atomica, 8400 Bariloche, ARGENTINA; telefax +54 944 45299; e-mail aligia@cab.cnea.edu.ar.
N. V. Anshukova, A. I. Golovashkin, L. I. Ivanova, O. T. Maljuchkov, and A. P. Rusakov, "Holes Localization, Electronic Structure and High-Tc Superconductivity." To be published in Physica C (in press). P. N. Lebedev Physical Institute, Russian Academy of Sciences, Leninsky Prospect 53, Moscow, RUSSIA. Key words: phase transition, heavy holes, superconductivity, local bosons, electron spectrum.
N. A. Babushkina, A. P. Zhernov, A. V. Inyushkin, T. N. Kulagina, V. I. Ozhogin, and L. V. Molchanova, "Anomalous Isotope Effect in High- Temperature Superconductor LSCO with 3-D Impurities." To be published in Physica C (in press). Russian Research Center "Kurchatov Institute", 123182 Moscow, RUSSIA; telefax +7 95 196 1632; e-mail ovi@ozhogin.kiae.zu. Key words: isotope effect, pair breaking, phonon mechanism, spin fluctuation, substitution effect.
A. M. Balagurov, V. Yu. Pomjakushin, V. G. Simkin, and A. A. Zakharov, "Neutron Diffraction Study of Phase Separation in La2CuO4+d Single Crystals." To be published in Physica C (in press). Frank Laboratory of Neutron Physics, JINR, 141980 Dubna, Moscow Region, RUSSIA; telefax +7 09621 65882; e-mail bala@nf.jinr.ru. Key words: phase separation, La2CuO4+d, neutron Fourier diffractometer, high resolution, single crystal.
T. Bauch, S. Weiss, H. Haensel, A. Marx, D. Koelle, and R. Gross, "High- Temperature Superconducting Josephson Vortex Flow Transistors: Numerical Simulations and Experimental Results." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996; to be published in IEEE Trans. Appl. Supercond. Contact R. Gross, Universitaet zu Koeln, II. Physikalisches Institut, Zuelpicher Str. 77, D-50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni-koeln.de.
A. V. Bazhenov, C. B. Rezchikov, and I. S. Smirnova, "Lattice Dynamics of the La2CuO4 Cmca Orthorhombic Phase at k=0." To be published in Physica C (in press). Contact I. S. Smirnova, Institute of Solid State Physics, Russian Academy of Sciences, Chernogolovka, Moscow District 142432, RUSSIA; telefax +7 096 576 4111; e-mail smirnova@issp.ac.ru. Key words: normal modes, nonsymmorphic group, IR spectrum.
M. Bjoernander, J. Magnusson, P. Svedlindh, P. Nordblad, D. P. Norton, and F. Wellhofer, "Frequency Dependence of the ac-Sheet Conductivity in Thin YBa2Cu3O7-d Films." To be published in Physica C (in press). Contact J. Magnusson, Department of Technology, Uppsala University, Box 534, S-751 21 Uppsala, SWEDEN; telephone +46 18 183135; telefax +46 18 500131; e-mail johan.magnusson@teknikum.uu.se. Key words: thin films, ac sheet conductivity, fluctuation effects, Kosterlitz-Thouless theory. 74.40.+k; 74.25.Nf; 74.76.Bz.
H. Bocuk, B. A. Albiss, I. Ercan, H. Ozkan, and N. Gasanly, "Effect of Magnetic Field and Temperature on the Voltage-Current Characteristics of YBCO Superconductor." To be published in J. Low Temp. Phys. Department of Physics, Middle East Technical University, 06531 Ankara, TURKEY; I. Ercan's telefax +90 312 8154307.
J. Bouvier and J. Bok, "The van Hove Scenario of High Tc Superconductors: The Effect of Doping." Submitted to Physica C. Laboratoire de Physique du Solide UPR 5 CNRS ESPCI, 10, rue Vauquelin, F-75231 Paris Cedex 05, FRANCE; telephone +33 1 4079 4451; telefax +33 1 4079 4425; e-mail jacqueline.bouvier@espci.fr.
A. Bram, J. Markl, I. P. Makarova, H. Burzlaff, G. Saemann-Ischenko, and V. I. Simonov, "Changes in the Distribution of Electron Density in Nd2- xCexCuO4-d (x=0.13) During Cooldown." To be published in Physica C (in press). European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble, FRANCE; telefax +33 7688 2542.
A. Buzdin and V. Dorin, "Magnetic Field Crossover Between 2D and 3D Regimes of Gaussian Fluctuations in Layered Superconductors." To be published in the Proc. of the Adriatico Res. Conf. and NATO Adv. Res. Workshop on Fluctuation Phenomena in HTSC, Trieste, Italy, Aug. 5-8, 1996. Centre de Physique Theorique et de Modelisation, Universite Bordeaux I, CNRS-URA 1537, F-33174 Gradignan, Cedex, FRANCE; e-mail buzdin@bortibm1.in2p3.fr.
A. I. Buzdin and H. Kachkachi, "Generalized Ginzburg-Landau Theory for Non-Uniform FFLO Superconductors." Submitted to Phys. Lett. A. Centre de Physique Theorique et de Modelisation, Universite Bordeaux I, CNRS- URA 1537, F-33174 Gradignan, Cedex, FRANCE; e-mail buzdin@bortibm1.in2p3.fr. Key words: non-uniform superconducting state, paramagnetic limit, generalized Ginzburg-Landau functional. 74.60.Ec.
P. Chaddah and K. V. Bhagwat, "The Minimum-Flux-Change Criterion for the Electromagnetic Response of Hard Superconductors." Presented at the Int. Symposium on Advances in Supercond.: New Materials, Critical Currents, and Devices, Tata Institute of Fundamental Research, Mumbai, India, Sept. 17-20, 1996. Low Temperature Physics Group, Centre for Advanced Technology, Indore 452013, INDIA.
J. M. Chen, R. S. Liu, and S. F. Hu, "Electronic Structure in (Hg0.5Pb0.5)Sr2(Ca1-xYx)Cu2O7 Compounds Studied by Soft X-Ray Absorption Spectroscopy." To be published in Physica C (in press). Synchrotron Radiation Research Center (SRRC), Hsinchu, Taiwan, REPUBLIC OF CHINA.
C. W. Chu, Z. L. Du, Y. Cao, Y. Y. Xue, Y. Y. Sun, I. A. Rusakova, and L. Gao, "126 K Superconducting Phase in the Ba-Ca-Cu-O System." Preprint #96:126; to be published in Philos. Mag. Texas Center for Superconductivity, University of Houston, Houston, TX 77204-5932; telephone (713) 743-8200; telefax (713) 743-8201; e-mail preprints@www.tcs.uh.edu. Key words: high-temperature superconductivity, Ba-Ca-Cu-O, HTS cuprates, HTS synthesis, high- pressure synthesis.
M. Ciszek, S. P. Ashworth, B. A. Glowacki, A. M. Campbell, and P. Haldar, "Transport ac Losses in Multifilamentary Ag/Bi-2223 Tapes in Low External dc Magnetic Fields." To be published in Physica C (in press). IRC in Superconductivity, University of Cambridge, Cambridge CB3 0HE, UNITED KINGDOM. Key words: high-Tc superconductors, ac losses, critical current, superconducting tapes. 74.60.Jg; 74.72.Hs; 74.72.Fq; 85.25.Kx.
K. Y. Constantinian, G. A. Ovsyannikov, A. D. Mashtakov, J. Ramos, Z. G. Ivanov, J. Mygind, and N. F. Pedersen, "Microwave Dynamics of YBCO Bi- Epitaxial Josephson Structures." To be published in Physica C (in press). Institute of Radio Engineering and Electronics, RAS, Mokhovaya 11, Moscow 103907, RUSSIA; telefax +7 095 2038414; e-mail karen@hitech.cplire.ru. Key words: Josephson effect, grain boundaries, arrays, spectrum.
L. P. Cook, W. Wong-Ng, and M. Paranthaman, "Melting and Vaporization of the 1223 Phase in the System (Tl-Pb-Ba-Sr-Ca-Cu-O)." To be published in NIST J. Res. Contact W. Wong-Ng, A215 MATLS, National Institute of Standards and Technology, Gaithersburg, MD 20899-0001; telephone (301) 975-5791; telefax (301) 990-8729; e-mail wongng@tiber.nist.gov. Key words: melting point, phase equilibria, thallia vapor pressure, Tl-Pb- Ba-Sr-Ca-Cu-O system, 1223 superconductor.
E. Dantsker, S. Tanaka, P.-A. Nilsson, R. Kleiner, and John Clarke, "Reduction of 1/f Noise in High-Tc dc Superconducting Quantum Interference Devices Cooled in an Ambient Magnetic Field." To be published in Appl. Phys. Lett. Department of Physics, University of California, Berkeley, CA 94720; telephone (510) 642-3634; telefax (510) 642-1304; e-mail dantsker@physics.berkeley.edu. 74.76.Bz; 85.25.Dq.
A. Di Chiara, F. Lombardi, F. Miletto Granozio, U. Scotti di Uccio, M. Valentino, F. Tafuri, A. Del Vecchio, M. F. De Riccardis, and L. Tapfer, "Structure and Morphology of MgO/YBCO Bilayers for Biepitaxial Junctions." To be published in Physica C (in press). Contact U. Scotti di Uccio, Dipartamento Scienze Fisiche dell'Universita Federico II di Napoli, Napoli, ITALY; telefax +39 81 2391821; e-mail scotti@mvxna2.dsfing.unina.it.
H. Ding, M. R. Norman, T. Yokoya, T. Takeuchi, M. Randeria, J. C. Campuzano, T. Takahashi, T. Mochiku, and K. Kadowaki, "Evolution of the Fermi Surface with Carrier Concentration in Bi2Sr2CaCu2O8+d." Department of Physics, University of Illinois at Chicago, Chicago, IL 60607. 71.25.Hc; 74.25.Jb; 74.72.Hs; 79.60.Bm.
S. G. Doettinger, R. P. Huebener, and S. Kittelberger, "The Kramer-Pesch Effect and Damping of the Vortex Motion in the Cuprate Superconductors." Submitted to Phys. Rev. B. Physikalisches Institut, Lehrstuhl Experimentalphysik II, Universitaet Tuebingen, Morgenstelle 14, D-72076 Tuebingen, GERMANY. 74.25.Fy; 74.76.Bz; 74.60.Ge.
A. V. Dooglav, H. Alloul, M. V. Eremin, and A. G. Volodin, "NMR Study of the Low Temperature Magnetic Excitations in RBa2(Cu1-yNiy)3O6 (R=Y,Tm)." To be published in Physica C (in press). Contact H. Alloul, Laboratoire de Physique des Solides, UA2 CNRS, Universite Paris-Sud, F-91405 Orsay Cedex, FRANCE; telefax +33 1 69 41 60 86; e-mail alloul@lps.u-psud.fr. Key words: antiferromagnetic order, NMR spin-lattice relaxation time, spin fluctuations, substitution effects, defects.
S. X. Dou, X. L. Wang, Y. C. Guo, Q. Y. Hu, P. Mikheenko, J. Horvat, M. Ionescu, and H. K. Liu, "Introduction of Pinning Centers into Bi-(Pb)- Sr-Ca-Cu-O Superconductors." Institute of Materials Technology and Manufacturing, University of Wollongong, Northfields Avenue, Wollongong NSW 2522, AUSTRALIA; telephone +61 42 21 4566; telefax +61 42 21 4577; e-mail s.dou@uow.edu.au.
H. S. Edelman, J. A. Parrell, and D. C. Larbalestier, "Evolution of the Transport Critical Current Density and Irreversibility Field as a Function of Heat Treatment and Pressing Pressure During Processing of Ag-Sheathed (Bi,Pb)2Sr2Ca2Cu3Ox Tapes." To be published in J. Appl. Phys. Applied Superconductivity Center and Department of Physics, University of Wisconsin, Madison, WI 53706.
R. Eder, Y. Ohta, and G. A. Sawatzky, "Doping Dependent Quasiparticle Band Structure in Cuprate Superconductors." Department of Applied and Solid State Physics, University of Groningen, Nijenborgh 4, 9747 AG Groningen, THE NETHERLANDS; e-mail eder@vsf1.phys.rug.nl. 74.20.-z; 75.10.Jm; 75.50.Ee.
V. J. Emery, S. A. Kivelson, and O. Zachar, "Spin-Gap Proximity Effect Mechanism of High Temperature Superconductivity." Preprint #BNL-63578. Department of Physics, Brookhaven National Laboratory, Upton, NY 11973; preprint also available at cond-mat@xxx.lanl.gov (#9610094).
M. R. Eskildsen, P. L. Gammel, B. P. Barber, U. Yaron, A. P. Ramirez, D. A. Huse, D. J. Bishop, C. Bolle, C. M. Lieber, S. Oxx, S. Sridhar, N. H. Andersen, K. Mortensen, and P. C. Canfield, "Observation of a Field- Driven Structural Phase Transition in the Flux Line Lattice in ErNi2B2C." Submitted to Phys. Rev. Lett. Department of Solid State Physics, Riso National Laboratory, DK-4000 Roskilde, DENMARK.
N. I. Firsov, I. L. Novikov, and V. S. Shadrin, "Crystal Structure, Electron Spectrum and Superconductivity of YBaCuO." Presented at the 5th World Congress on Superconductivity, Budapest, Hungary, July 7 - 11, 1996; to be published in Superlatt. and Microstruc. Department of Semiconductive Devices and Microelectronics, Novosibirsk State Technical University, 20 Karl Marx Prospect, Novosibirsk 630092, RUSSIA; e-mail sdm@nstu.nsk.su. Key words: high-temperature superconductivity, crystal structure, electron spectrum, yttrium.
F. C. Fritschij, H. B. Brom, L. J. de Jongh, A. Tighezza, J. L. Rehspringer, and M. Drillon, "[19]^F NMR on Pr2CuO4-xFx and Nd2CuO4- xFx." To be published in Physica C (in press). Contact H. B. Brom, Kamerlingh Onnes Laboratory, Leiden University, P.O. Box 9506, 2300 RA Leiden, THE NETHERLANDS; telefax +31 71 5275404; e-mail brom@rulkol.leidenuniv.nl. Key words: electron-doped superconductor, NMR.
O. M. Froehlich, A. Beck, R. Gross, H. Sato, and M. Naito, "In-plane Penetration Depth of High Temperature Superconductors with Single and Double CuO Layers." To be published in Europhys. Lett. Contact R. Gross, II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni-koeln.de. 85.25.Cp; 74.50.+r; 85.70.-w.
O. M. Froehlich, A. Beck, P. Richter, and R. Gross, "Precision Measurement of the ab-Plane London Penetration Depth in High Temperature Superconducting Thin Films." Presented at the XXI Int. Conf. on Low Temp. Phys. (LT21), Prague, Czech Republic, Aug. 8-14, 1996; to be published in Czech. J. Phys., Vol. 46. Contact R. Gross, II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D- 50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni-koeln.de.
O. M. Froehlich, P. Richter, A. Beck, R. Gross, and G. Koren, "Quasiparticle Tunneling in HTS Bicrystal Grain Boundary Junctions." Presented at the XXI Int. Conf. on Low Temp. Phys. (LT21), Prague, Czech Republic, Aug. 8-14, 1996; to be published in Czech. J. Phys., Vol. 46. Contact R. Gross, II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni-koeln.de.
O. M. Froehlich, P. Richter, A. Beck, D. Koelle, and R. Gross, "Barrier Properties of Grain Boundary Junctions in High-Tc Superconductors." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996; to be published in IEEE Trans. Applied Supercond. Contact R. Gross, II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni-koeln.de.
Hiroyuki Fuke, Kazuo Saitoh, Tadashi Utagawa, and Youichi Enomoto, "Fundamental Operation of Single-Flux-Quantum Circuits Using Coplanar Type High-Tc SQUID'S." To be published in Appl. Phys. Lett. Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717.
R. Gerber, T. Nissel, H.-G. Wener, A. Willmann, S. Keil, H. Haensel, R. P. Huebener, D. Koelle, and R. Gross, "Low-Temperature Scanning Electron Microscopy for Low Noise Studies of High-Tc Superconductors." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996; to be published in IEEE Trans. Applied Supercond. Contact R. Gross, II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni-koeln.de.
E. A. Goodilin, N. N. Oleynikov, E. V. Antipov, R. V. Shpanchenko, G. Yu. Popov, V. G. Balakirev, and Yu. D. Tretyakov, "On the Stability Region and Structure of the Nd1-xBa2-xCu3Oy Solid Solution." To be published in Physica C (in press). Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717. Key words: neodymium solid solution, stability region, structural evolution, ordering.
I. K. Gopalakrishnan and J. V. Yakhmi, "Irreversibility Characteristics of the Tl-Monolayer 1212 Cuprate Superconductors." Presented at the Int. Symposium on Advances in Supercond.: New Materials, Critical Currents, and Devices, Tata Institute of Fundamental Research, Mumbai, India, Sept. 17-20, 1996. Chemistry Division, Bhabha Atomic Research Centre, Mumbai 400 085, INDIA; J. V. Yakhmi's telephone +91 22 556-9339 or -3060, ext. 2232; telefax +91 22 556-0750 or -0534; e-mail yakhmi@magnum.barct1.ernet.in.
L. P. Gor'kov and P. Kumar, "Back to a Mean Field Hole Spectrum in the Three Band Model." National High Magnetic Field Laboratory, Florida State University, 1800 E. Paul Dirac Dr., Tallahassee, FL 32306-4005.
R. Gross, L. Alff, A. Beck, O. M. Froehlich, D. Koelle, and A. Marx, "Physics and Technology of High Temperature Superconducting Josephson Junctions." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996; to be published in IEEE Trans. Applied Supercond. Contact R. Gross, II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni- koeln.de.
A. Gupta, E. D. Tuset, M. G. Karkut, and K. Fossheim, "Short Time Magnetic Relaxation in Bi2Sr2Ca2Cu3O10 Tapes: A Study of Thermally Activated Flux Motion and Vortex Glass Transition." To be published in Physica C (in press). LPMC, Universite de Picardie Jules Verne, 33 rue Saint-Leu, F-80039 Amiens, FRANCE.
*Ernst L. Haase, "The Violation of the BCS Theory and the Extensions Required to Include the Effects of a Nearby Phase Transition." To be published in the Proc. of Phys. and Mater. Sci. in High Temp. Supercond. IV; NATO Advanced Research Workshop, Strbske Pleso, High Tatra Mountains, Slovak Republic, July 21-27, 1996. Forschungszentrum Karlsruhe, IMF III, D-76021 Karlsruhe, GERMANY; telephone +49 7247-82 2807; telefax +49 7247-82 3956; e-mail haase@imf.fzk.de. *Updated Version.
H. Haensel, C. Hoefener, D. Koelle, and R. Gross, "Fabrication and Characterization of YBa2Cu3O7-d/SrTiO3/Ag Trilayer Films on SrTiO3 Bicrystal Substrates." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996; to be published in IEEE Trans. Applied Supercond. Contact R. Gross, II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni-koeln.de.
R. Hauff, S. Tajima, W.-J. Jang, and A. I. Rykov, "Optical Study on Phonon Anomalies and Spin Gap in YBa2(Cu1-xZnx)3O6.6." Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717. 74.25.Gz; 74.72.Bk; 78.30.Er; 63.20.Kr.
R. Hiergeist and R. Hergt, "Evidence for Different Regimes of Collective Flux Line Pinning in YBa2Cu3O7-d Single Crystals." To be published in Phys. Rev. B. Institut fuer Physikalische Hochtechnologie e.V. Jena, Postfach 100 239, D-07702 Jena, GERMANY; e-mail hiergeist@main.ipht- jena.de. 74.60.Ge; 74.60.Jg; 74.72.Bk.
M. D. Hill, J. E. Blendell, and L. H. Bennett, "Reduced Microcrack Density in Melt Processed (Y,Sm)Ba2Cu3O6+x." To be published in Physica C (in press). Ceramics Division and Metallurgy Division, Materials Science and Engineering Laboraory, National Institute of Standards and Technology, Gaithersburg, MD 20899.
B. M. Hinaus, R. D. Redwing, and M. S. Rzchowski, "Flux Penetration in Bicrystal-Substrate Thin-Film YBCO Josephson Junctions." To be published in Appl. Phys. Lett. Department of Physics and Applied Superconductivity Center, University of Wisconsin-Madison, 1150 University Avenue, Madison, WI 53706; M. S. Rzchowski's telephone (608) 265-2876; telefax (608) 265-2334; e-mail mark@cheddar.physics.wisc.edu. 74.50.+r; 74.60.Ge; 74.60.Jg; 74.72.Bk.
Anming Hu, Sunlian Jia, Hong Chen, and Zhongxian Zhao, "Superconducting Behaviors of Melt Textured Nd1+xBa2-xCu3Oy Undergoing Heat Treatments in Flowing Argon and Oxygen." To be published in Physica C (in press). National Laboratory for Superconductivity, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, PEOPLE'S REPUBLIC OF CHINA. Key words: melt-textured materials, Nd1+xBa2-xCu3Oy, argon atmosphere.
John R. Hull, Thomas M. Mulcahy, and Joseph F. Labataille, "Velocity Dependence of Rotational Loss in Evershed-Type Superconducting Bearings." To be published in Appl. Phys. Lett. Contact Janice Coble, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439; telefax (708) 252-9595; e-mail janice_coble@qmgate.anl.gov.
M. Isobe, Y. Matsui, and E. Takayama-Muromachi, "New Series of Oxyphosphate Superconductors (Cu0.5P0.5)Sr2(Ca,Y)n-1CunOy((Cu,P)-12(n- 1)n, n=3-6) Prepared Under High Pressure." To be published in Physica C (in press). National Institute for Research in Inorganic Materials (NIRIM), 1-1 Namiki, Tsukuba, Ibaraki 305, JAPAN; telefax +81 298 52 7499; e-mail misobe@nirim.go.jp. Key words: oxyphosphate superconductors, high-pressure synthesis, HRTEM, magnetic susceptibility, electric resistivity.
Alpo Kallio, Victor Sverdlov, and Karoliina Honkala, "Some New Aspects of High-Tc Superconductors: Chemical Equilibrium." To be published in Superlatt. and Microstruc. (in press). Department of Physical Sciences, Theoretical Physics Division, University of Oulu, Oulu, FINLAND.
Alpo Kallio, Victor Sverdlov, and Martti Rytivaara, "Paramagnetic Meissner Effect and Time Reversal Non-Invariance from Spin Polarization." To be published in Superlatt. and Microstruc. (in press). Department of Physical Sciences, Theoretical Physics Division, University of Oulu, Oulu, FINLAND.
Maarit Karppinen, Hisao Yamauchi, and Lauri Niinistoe, "Oxygen Stoichiometry and Copper Valency in Superconducting Cuprates Studied by Chemical Methods." Presented at the 9th Int. Symposium on Supercond. (ISS'96), Sapporo, Hokkaido, Japan, Oct. 21-24, 1996; to be published in Adv. Supercond. IX (Springer-Verlag, Tokyo). Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226, JAPAN; Hisao Yamauchi's telephone +81 45-924 5315; telefax +81 45-921 6953 or -924-5360; e-mail yamauchi@materia.titech.ac.jp. Key words: oxygen stoichiometry, copper valency, chemical analysis.
G. Krabbes, P. Schaetzle, W. Bieger, G. Fuchs, U. Wiesner, and G. Stoever, "Thermodynamically Controlled Melt Processing to Improve Bulk Materials." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996; to be published in IEEE Trans. Applied Supercond. Institut fuer Festkoerper- und Werkstofforschung e. V., Postfach 270016, D-01171 Dresden, GERMANY.
Vladimir Z. Kresin, Andreas Bill, Stuart A. Wolf, and Yu. N. Ovchinnikov, "Novel Isotope Effects in Superconductors." Lawrence Berkeley National Laboratory, University of California, 1 Cyclotron Road, Berkeley, CA 94720.
Pradeep Kumar, "Properties of Phase Transitions of a Higher Order." Division of Materials Research, National Science Foundation, 4201 Wilson Boulevard, Arlington, VA 22230; e-mail pkumar@nsf.gov; preprint also available at cond-mat@xxx.lanl.gov (#9611047).
Kiyoshi Kuroda, In-Hwan Choi, Hiromi Unoki, and Naoki Koshizuka, "NdBa2Cu3O7-d Single Crystal Growth by the Traveling-Solvent Floating- Zone Method." Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5707; telefax +81 3 3536-5714; e-mail k-kuroda@mmc.co.jp. Key words: crystal growth, traveling-solvent floating-zone method, NdBa2Cu3O7-d. 74.72.Jt; 81.10.- h.
Th. Lang, D. Buhl, and L. J. Gauckler, "Melting of Bi-2212 Under Controlled Oxygen Partial Pressures with Silver." Submitted to Physica C. Nonmetallic Materials, ETH Zurich, Sonneggstrasse 5, CH-8092 Zurich, SWITZERLAND; telephone +41 1 632 5651; telefax +41 1 632 1132; e-mail lang@nonmet.mat.ethz.ch. Key words: Bi2Sr2CaCu2Ox, superconductor, silver, melting, oxygen partial pressure.
Ekkehard Lange, "Memory Function Approach to the Hall Constant in Strongly Correlated Electron Systems. Part II." To be published in Phys. Rev. B. Institut fuer Theorie der Kondensierten Materie, Universitaet Karlsruhe, D-76128 Karlsruhe, GERMANY; e-mail lange@tkm.physik.uni-karlsruhe.de; preprint also available at cond- mat@xxx.lanl.gov (#9611050).
D.S-L. Law, M. N. Mikheeva, V. G. Nazin, A. V. Svishchev, M. B. Tsetlin, N. Hayes, and S. Downes, "Resonance Photoelectron Emission Near the Excitation Threshold of Lanthanum 5p States for La2CuO4+x and Related Compounds." To be published in Physica C (in press). Daresbury Laboratory, CLRC, WA4 4AD, Warrington, Cheshire, UNITED KINGDOM. Key words: resonance photoemission, UPS, electronic structure, La, La2CuO4+x, La2NiO4+y, Nd2CuO4.
Sang Young Lee, J. Y. Cho, Y. H. Kim, B. J. Soh, B. H. Park, J. W. Ahn, C. S. Jung, T. S. Hahn, S. S. Choi, B. Oh, S. H. Moon, V. B. Fedorov, and A. G. Denisov, "Microwave Properties of High-Tc YBa2Cu3O7-d Microstrip Resonators with Different Surface Morphologies and Finite Thickness." To be published in Physica C (in press). Department of Physics and Center for Advanced Materials and Devices, Kon-Kuk University, Seoul, 143-701, KOREA. Key words: surface impedance, YBa2Cu3O7-d, thin films, London penetration depth, microwave properties.
C. T. Lin, A. M. Niraimathi, Y. Yan, K. Peters, H. Bender, E. Schoenherr, and E. Gmelin, "Single Crystals of Nd1+xBa2-xCu3-yGayO7-d and Their Characterization." To be published in Physica C (in press). Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, D- 70569 Stuttgart, GERMANY.
K. Maki and M. T. Beal-Monod, "Ginzburg Landau Equation and the Upper Critical Field in Anisotropic d+s Wave Superconductivity." Submitted to Phys. Rev. B. Department of Physics and Astronomy, University of Southern California, Los Angeles, CA 90089-0484; M. T. Beal-Monod's telephone at Orsay, France +33 1 69 15 69 28; telefax +33 1 69 15 60 86.
A. Marx, L. Alff, and R. Gross, "Low Frequency Voltage Noise in High Temperature Superconductor Josephson Junctions." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996; to be published in IEEE Trans. Appl. Supercond. Contact R. Gross, II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D- 50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni-koeln.de.
C. Meingast, T. Wolf, M. Klaeser, and G. Mueller-Vogt, "Uniaxial Pressure Dependence of Tc in (Y1-yCay )1Ba2Cu3Ox Single Crystals Via High-Resolution Thermal Expansion." To be published in the Proc. of the Int. Conf. on Phys. and Chem. of Molecular and Oxide Supercond. (MOS'96), Karlsruhe, Germany, Aug. 2-6, 1996. Forschungszentrum Karlsruhe, Institut fuer Nukleare Festkoerperphysik, P.O. Box 3640, D- 76021 Karlsruhe, GERMANY; telephone +49 7247 82 2188; telefax +49 7247 82 4624; e-mail meinga@infp.fzk.de.
Y. Morita, M. Kohmoto, and K. Maki, "Quasi-Particle Spectra Around a Single Vortex in a d-Wave Superconductor." Institute for Solid State Physics, University of Tokyo, 7-22-1 Roppongi, Minato-ku, Tokyo 106, JAPAN.
Y. Moriwaki, T. Sugano, C. Gasser, A. Fukuoka, K. Nakanishi, S. Adachi, and K. Tanabe, "Epitaxial HgBa2Ca2Cu3Oy Films on SrTiO3 Substrates Prepared by Spray Pyrolysis Technique." To be published in Appl. Phys. Lett. Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717.
Y. Moriwaki, T. Tatsuki, A. Tokiwa-Yamamoto, T. Tamura, S. Adachi, and K. Tanabe, " High Pressure Synthesis of HgBa2Ca2Cu3O7 Without a Precursor." Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717.
Shin'ichi Morohashi, Tadashi Utagawa, and Youichi Enomoto, "A High-Tc Josephson Junction on a Narrow Tungsten Line Formed by Focused Ion Beam- Chemical Vapor Deposition." Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717.
Edmund Soji Otabe, Ryouhei Kitamura, and Teruo Matsushita, "ac Susceptibility Measurements for Superconducting Y-Ba-Cu-O Powder." To be published in Jpn. J. Appl. Phys. Department of Computer Science and Electronics, Kyushu Institute of Technology, 680-4 Kawazu Iizuka, Fukuoka 820, JAPAN; telephone/telefax +81 948 29 7683; e-mail otabe@cse.kyutech.ac.jp. Key words: third harmonic ac susceptibility, reversible fluxoid motion. Y-Ba-Cu-O, critical current density, Campbell's penetration depth.
M. H. Pedersen, J. J. Rodriguez-Nunez, H. Beck, T. Schneider, and S. Schafroth, "Superconducting Properties of the Attractive Hubbard Model." To be published in Z. Phys. B. Department de Physique Theorique, Universite de Geneve, CH-1211 Geneve, SWITZERLAND. 74.20.Fg; 74.20.-z; 74.60.-w; 74.72.-h.
M. Polak, W. Zhang, A. Polyanskii, A. Pashitski, E. E. Hellstrom, and D. C. Larbalestier, "The Effect of the Maximum Processing Temperature on the Microstructure and Electrical Properties of Melt Processed Ag- Sheathed Bi2Sr2CaCu2Ox Tape." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996. Applied Superconductivity Center, College of Engineering, University of Wisconsin-Madison, 1500 Johnson Drive, Madison, WI 53706-1687; telephone (608) 263-1580; telefax (608) 263-1087.
V. Yu. Pomjakushin, A. A. Zakharov, A. Amato, V. N. Duginov, F. N. Gygax, D. Herlach, A. N. Ponomarev, and A. Schenck, "Spin-Glass Ordering in Non-Phase-Separated La2CuO4.03 Studied by muSR." To be published in Physica C (in press). Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region, RUSSIA. Key words: muon spin rotation, phase separation, oxygen stoichiometry, spin-glass state, La2CuO4+y.
J.J.M. Pothuizen, R. Eder, M. Matoba, G. A. Sawatzky, N. T. Hien, and A. A. Menovsky, "Single Hole Dynamics in the CuO2-Plane at Half-Filling." Submitted to Phys. Rev. Lett. Contact R. Eder, Surface Science, Materials Science Center, University of Groningen, Nijenborgh 4, 9747 AG Groningen, THE NETHERLANDS; e-mail eder@vsf1.phys.rug.nl. 74.25.Jb; 79.60.Bm; 74.72.Jt.
P. Richter, A. Beck, O. M. Froehlich, R. Gross, and G. Koren, "Conductance Zero Bias Anomaly in High Temperature Superconducting Grain Boundary Josephson Junctions." Presented at the XXI Int. Conf. on Low Temp. Phys. (LT21), Prague, Czech Republic, Aug. 8-14, 1996; to be published in Czech. J. Phys., Vol. 46 (1996). Contact R. Gross, II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D- 50937 Koeln, GERMANY; telephone +49 221 470 2707; telefax +49 221 470 5178; e-mail gross@colorix.ph2.uni-koeln.de.
A. Sacuto, R. Combescot, N. Bontemps, P. Monod, V. Viallet, and D. Colson, "Nodes of the Superconducting Gap Probed by Electronic Raman Scattering in HgBa2CaCu2O6+d Single Crystals." Submitted to Phys. Rev. Lett. LPMC, P13, Ecole Normale Superieure, 24 rue Lhomond, F-75231 Paris Cedex 05, FRANCE; telephone +33 1 44 32 25 55; e-mail alsa@physique.ens.fr. 74.25.Gz; 74.72.Jt; 78.30.Er.
Kazuo Saitoh, Hiroyuki Fuke, Tadashi Utagawa, and Youichi Enomoto, "Logic Operation Using a High Tc Coupled Superconducting Quantum Interference Device." Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717. Key words: rf SQUID, dc SQUID, AND/OR logic, NdBa2Cu3O7-d, focused ion beam.
S. Sarti, M. Giura, E. Silva, R. Fastampa, and V. Boffa, "Experimental Determination of the Fluctuational Dissipation in YBCO up to High Magnetic Fields." To be published in Phys. Rev. B. Dipartimento di Fisica and INFM, Universita "La Sapienza", Piazzale Aldo Moro 2, I-00185 Roma, ITALY; telefax +39 6 4463158; e-mail sarti@roma1.infn.it. 74.25.Fy; 74.40.+k; 74.76.Bz.
S. Schafroth, J. J. Rodriguez-Nunez, and H. Beck, "Some Global Properties of the Attractive Hubbard Model in the Superconducting Phase: T-Matrix Approximation in 2D." Submitted to J. Phys. Condens. Matter. Physik-Institut der Universitaet Zurich, Winterthurerstrasse 190, CH- 8057 Zurich, SWITZERLAND. 74.20.Mn; 74.25.-q; 74.72.-h.
V. Selvamanickam, K. Pfaffenbach, D. Kirchoff, M. Gardner, D. W. Hazelton, and P. Halder, "Development of Tl-1223 Conductors for 77 K HTS Applications." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996; to be published in IEEE Trans. Applied Supercond. Intermagnetics General Corporation, 450 Old Niskayuna Rd., P.O. Box 461, Latham, NY 12110.
A. Serquis, F. Prado, and A. Caneiro, "Copper Nonstoichiometry at High Temperatures in Nd1.85Ce0.15Cu1+-dOy." To be published in Physica C (in press). Contact A. Caneiro, Centro Atomico Bariloche, CNEA, 8400 Bariloche, ARGENTINA. Key words: electron-doped superconductors, cationic defects, phase diagrams. 74.62.Bf; 74.62.Dh.
S. Tajima, J. Schuetzmann, S. Miyamoto, I. Terasaki, Y. Sato, and R. Hauff, "Optical Study of c-Axis Charge Dynamics in YBa2Cu3Oy: Carrier Self-Confinement in the Normal and the Superconducting States." To be published in Phys. Rev. B. Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717. 74.25.Gz; 74.72.Bk; 78.30.Er.
T. Tatsuki, A. Tokiwa-Yamamoto, T. Tamura, X.-J. Wu, Y. Moriwaki, S. Adachi, and K. Tanabe, "Structural and Superconducting Properties of (Hg1-xTlx)2Ba2Can-1CunOy (n=3, 4) Superconductors Prepared Under a High Pressure." To be published in Physica C (in press). Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717.
J. R. Thompson, H. R. Khan, and K. J. Song, "Influence of Ag-Additions on the Superconducting Properties of HgBa2CuO4+d Materials: Hole Doping and Surface Barrier Effects." To be published in Physica C (in press). Oak Ridge National Laboratory, P.O. Box 2008, Bldg. 3115, Oak Ridge, TN 37831-6061; telephone and telefax (423) 574-0412; e-mail jrt@utk.edu. Key words: magnetization, flux creep, hole concentration, London penetration depth, surface barrier. 74.25.Ha; 74.60.Ec; 74.60.Ge; 74.62.Dh.
Carsten Timm, "Flux Noise in High-Temperature Superconductors." To be published in Phys. Rev. B. Universitaet Hamburg, I. Institut fuer Theoretische Physik, Jungiusstrasse 9, D-20355 Hamburg, GERMANY; e-mail timm@gibbs.physics.indiana.edu; preprint also available at cond- mat@xxx.lanl.gov. (#9610205). 74.40.+k; 74.20.De; 74.72.Hs; 74.60.Ge.
Z. Tomkowicz, M. Balanda, A. Zaleski, A. W. Pacyna, and A. Szytula, "Superconductivity Suppression in the Ho(Pr)Ba2Cu3O7-d System." Institute of Physics, Jagellonian University, Reymonta 4, PL-30-059 Krakow, POLAND.
Z. Tomkowicz, E. Sciesinska, J. Sciesinski, P. Lunkenheimer, M. Dumm, M. Balanda, and A. Szytula, "Charge Carriers Localization Study in the R(Pr)Ba2Cu3O7-d System in the Aspect of Superconductivity Suppression." Institute of Physics, Jagellonian University, Reymonta 4, PL-30-059 Krakow, POLAND.
Ola Toernkvist and Elsebeth Schroeder, "Vortex Dynamics in Dissipative Systems." NASA/Fermilab Astrophysics Center, MS-209, P. O. Box 500, Batavia, IL 60510; e-mail olat@fnas07.fnal.gov; preprint also available at patt-sol (#9611001).
T. Tsuboi, T. Hanaguri, and A. Maeda, "Evidence of a Highly Viscous Vortex Liquid in Bi2Sr2CaCu2Oy." Submitted to Phys. Rev. B. Department of Basic Science, University of Tokyo, 3-8-1, Komaba, Meguro-ku, Tokyo 153, JAPAN; +81 3 5454 6763; telefax +81 3 3467 8945; e-mail cc67913@komaba.ecc.u-tokyo.ac.jp. 74.60.Ge; 74.25.Bt; 74.25.Fy; 74.72.Hs.
M. Verma and V. S. Tomar, "Comparison of Co and Ni Doping at Copper Sites in Y-124 High Temperature Superconductor." To be published in Physica C (in press). National Physical Laboratory, Dr. K. S. Krishnan Marg, New Delhi-110002, INDIA; telephone +91 11 578 7161; telefax +91 11 575 2678; e-mail npl@sirnetd.ernet.in. Key words: structural phase transition, substitution effects, O-T transition, Cu-O chains, Cu-O planes. 74.72.Bk; 74.62.Dh.
Nghia Van Vo, Hua Kun Liu, and Shi Xue Dou, "Construction and Normal Zone Propagation Analysis of High-Tc Superconducting Bi(Pb)-2223/Ag Class II Coils and Magnets." Presented at the Appl. Supercond. Conf. (ASC'96), Pittsburgh, PA, Aug. 25-30, 1996; to be published in IEEE Trans. Applied Supercond. Center for Superconducting and Electronic Materials, Institute of Materials Technology and Manufacturing, University of Wollongong, Northfields Avenue, Wollongong NSW 2522, AUSTRALIA.
X. L. Wang, H. K. Liu, and S. X. Dou, "Morphologies of Square Shape Spirals and (110) Twins in Spiral-Grown Bi2Sr2CaCu2Oy Crystals." To be published in Physica C. Center for Superconducting and Electronic Materials, Institute of Materials Technology and Manufacturing, University of Wollongong, Northfields Avenue, Wollongong NSW 2522, AUSTRALIA; telefax +61 42 213112; e-mail xlw01@uow.edu.au. Key words: single-crystal growth, spiral growth, growth twins.
H.-R. Wenk, D. Chateigner, M. Pernet, J. Bingert, E. Hellstrom, and B. Ouladdiaf, "Texture Analysis of Bi-2212 and 2223 Tapes and Wires by Neutron Diffraction." To be published in Physica C (in press). Department of Geology and Geophysics, University of California, Berkeley, CA 94720.
W. Wong-Ng, L. P. Cook, and F. Jiang, "Melting Equilibria of the Bi-Sr- Ca-Cu-O (BSCCO) System in Air. I. The Primary Crystallization Phase Field of 2212 Phase and the Effect of Ag Addition." Submitted to J. Am. Ceram. Soc. A215 MATLS, National Institute of Standards and Technology, Gaithersburg, MD 20899; telephone (301) 975-5791; telefax (301) 990- 8729; e-mail wongng@tiber.nist.gov.
Winnie Wong-Ng, Lawrence P. Cook, and Feng Jiang, "Subsolidus and Melting Study of the Bi2O3-PbOx-CuO System in Air." Submitted to Appl. Supercond. A215 MATLS, National Institute of Standards and Technology, Gaithersburg, MD 20899; telephone (301) 975-5791; telefax (301) 990- 8729; e-mail wongng@tiber.nist.gov.
Hisao Yamauchi and Maarit Karppinen, "Hole Doping Routes and Confined Net Holes in Superconducting Cuprates." Presented at the 9th Int. Symposium on Supercond. (ISS'96), Sapporo, Hokkaido, Japan, Oct. 21-24, 1996; to be published in Adv. Supercond. IX (Springer-Verlag, Tokyo). Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226, JAPAN; telephone +81 45-924 5315; telefax +81 45-921 6953 or -924 5360; e-mail yamauchi@materia.titech.ac.jp. Key words: charge balance, hole-doping routes, confined net holes, innermost CuO2 planes.
X. Yao, M. Nakamura, M. Tagami, and Y. Shiohara, "Growth Rate and Superconductivity of Y(Sm)BCO Single Crystals." To be published in Physica C (in press). Superconductivity Research Laboratory, International Superconductivity Technology Center (ISTEC), 10-13 Shinonome 1-chome, Koto-ku, Tokyo 135, JAPAN; telephone +81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717. Key words: superconductivity, single-crystal growth, substitution effects.
Shusuke Yomo, Masashi Kawakami, Huang-Hsu Feng, Zu-Gang Li, Pei-Herng Hor, and Nobuo Mori, "High Pressure Study of the Electric Transport Properties of Electrochemically Intercalated La2CuO4+d." Preprint #96:131; presented at the 9th Int. Symposium on Supercond. (ISS'96), Sapporo, Hokkaido, Japan, Oct. 21-24, 1996; to be published in Adv. Supercond. IX (Springer-Verlag, Tokyo). Texas Center for Superconductivity, University of Houston, Houston, TX 77204-5932; telephone (713) 743-8200; telefax (713) 743-8201; e-mail preprints@www.tcs.uh.edu. Key words: oxygen intercalation, high- temperature superconductivity, high pressure, Hall coefficient, La2CuO4+d.
Jan. 20 -21, 1997: Two one-day workshops. Jan. 20: Industrial Materials Processing; Jan. 21: Thin Film Growth by Laser Ablation; The Queen's University of Belfast, Belfast, Northern Ireland. Intended to follow workshops of previous years by considering commercial value and rapid development in laser-material applications such as thin-film growth and micromachining. Workshop 1 is devoted to bringing together academic and industrial communities that have an interest in use of lasers for materials synthesis, processing, and plasma physics. Workshop 2 will provide a forum to present and discuss issues relevant to the pulsed-laser deposition of thin films. Special session to review potential techniques and methods for in-situ monitoring and characterization during the PLD process. Poster sessions also. For information, contact Robert M. Bowman, Condensed Matter Physics & Materials Science Division, Department of Pure & Applied Physics, Queen's University of Belfast, Belfast BT7 1NN, Northern Ireland; telephone + 44 1232 273572; telefax + 44 1232 438918; e-mail r.m.bowman@qub.ac.uk; web site http://www.qub.ac.uk/math&p/cmp/qubpld.html.
Feb. 6 - 7, 1997: The DOE 1997 Wire Development Workshop, Marriott/Bay Point in Panama City, Florida. Objectives are to hear reports on research progress, trends, and problems in HTS coated conductor and powder-in-tube wire; review critical program needs and develop strategies for addressing issues in BSCCO wire and its applications, YBCO coated conductors, and low ac loss conductors; and interact with colleagues to further strengthen collaborative efforts in the program. Plenary sessions followed by working groups that address issues in that topical area. For more information, contact Jim Daley, Department of Energy, telephone (202) 586-1165; Chris Platt, Department of Energy, telephone (202) 586-8943; or Craig Matzdorf, Energetics, telephone (410) 290-0370.
*Feb. 28 - March 4, 1997: Fifth International Conference on Materials and Mechanisms of Superconductivity and High-Temperature Superconductors (M2S-HTSC-V), Beijing, China. Two plenary sessions, 30-33 microsymposia and oral sessions (three or four parallel sessions, at least two sessions to be reserved for latest new results and outstanding post deadline contributions), three tutorial sessions, and poster sessions. Topics include high-Tc materials; physical properties of high-Tc materials; magnetism and superconductivity; vortices, pinning, and flux melting; thin films and multilayers; Josephson junctions; applications; heavy fermions; organic superconductors; fullerenes; and theory. Exhibition of high-Tc superconducting materials, low-temperature experimental appliances, and cryogenic engineering and refrigeration instruments. Conference language is English. Abstract and manuscript deadline, January 31, 1997.** For information, contact D. Jin, M2S- HTSC-V Secretariat, Cryogenic Laboratory, Chinese Academy of Sciences, P.O. Box 2711, Beijing 100 080, People's Republic of China; telephone +86 10 6 255 1143; telefax +86 10 6 256 4049; e-mail djin@cl.cryo.ac.cn; web site http://sun1.bham.ac.uk/hey/conferences/. **Note revised abstract deadline and telephone numbers.
April 3 - 4, 1997: Workshop on ac Losses, San Francisco Marriott, San Francisco, CA. Sponsored by the Electric Power Research Institute (EPRI). Two-day workshop will cover theoretical and experimental research on power-line-frequency (50-60 Hz) ac losses in high- temperature superconductors, and the influence such losses have on the design of HTS devices for electric power applications. Will consist of talks, posters, and workshop discussions. No registration fee, but attendance limited to 50 participants. (Workshop will follow Symposium R: Materials Issues Related to Development of Textured High-Temperature Superconducting Conductors at the 1997 MRS Spring Meeting, being held April 1-2, 1997, at the same location.) Applications consisting of name, institution, address, phone and fax numbers, e-mail address, and abstract (using the MRS symposia format), will be used to select oral and poster presentations. For further information, contact one of the workshop organizers (preferably by e-mail): John R. Clem, A517 Physics, Iowa State University, Ames, IA 50011, telephone (515) 294-4223, telefax (515) 294-0689, e-mail clem@ameslab.gov; or Masaki Suenaga, Brookhaven National Laboratory, Bldg. 480, Upton, NY 11973, telephone (516) 282-3518, telefax (516) 282-4071, e-mail mas@sun2.bnl.gov. For separate information about the 1997 MRS Spring Meeting and accommodations, contact the Materials Research Society, 9800 McKnight Road, Pittsburgh, PA 15237-6006, telephone (412) 367-3003, telefax (412) 367-4373, e-mail stevens@mrs.org.
June 8 - 20, 1997: NATO Advanced Study Institute on Applications of Superconductivity, Hotel Alexandra, Loen, Norway. The scientific bases, technological issues, and market potential of all current and emerging applications will be considered. These will include the fabrication of cables and magnets; power conditioning and transmission; energy storage; microwave electronics; SQUID magnetometry in biomagnetism, geophysics, and nondestructive evaluation; and analog and digital circuitry. Cryogenic and materials issues will be covered. For information on financial assistance and/or application, contact Harold Weinstock, AFOSR/NE, Bolling AFB, DC 20332-8080; telefax (202) 767-4986; e-mail harold.weinstock@afosr.af.mil. (The preferred mode of communication is e-mail.)
June 26 - 28, 1997: Superconducting Materials Aspects : Research & Technology (SMART 97), Liege, Belgium. A satellite to the Third European Conference on Applied Superconductivity (EUCAS'97) to be held at Veldhoven, The Netherlands (June 30 - July 3, 1997). Topics will include phase chemistry, synthesis, crystal growth, thermal stability, pinning, texturing, applications, modeling, properties, and HTS materials. For information, contact Chantal Lacrosse, Conference Secretary, A.I.M. rue St. Gilles 31, B-4000 Liege, Belgium; telephone +32 4 222 2946; telefax +32 4 222 23 82; e-mail aimulg@misc.ulg.ac.be.
*June 30 - July 3, 1997: 3rd European Conference on Applied Superconductivity (EUCAS'97), Veldhoven, The Netherlands. Objective is to provide an up-to-date and comprehensive overview of research and development activities in applications of all classes of superconductors. Conference aims to encourage new cooperations on European and wider international levels. Will include 4 plenary sessions, 21 oral sessions, and 4 poster sessions with keynote lecture at the beginning of each oral session. One plenary session will be devoted to industrial applicability of superconductivity and industrial perspective. Program will be broadly divided into small-scale & electronic applications, and large-scale & power applications. Former category will include Josephson junctions, SQUIDs, digital applications, mixers/detectors, passive devices, oscillators, materials aspects related to superconducting electronics, system aspects, and other applications. Latter category will include fusion and SMES, detectors and accelerators, motors and generators, high magnetic fields, power applications, materials aspects related to large-scale applications, system aspects, and other applications. Abstract deadline, January 15, 1997. For general conference information, contact Convention Bureau Basics, P.O. Box 217, 7500 AE, Enschede, The Netherlands; telephone +31 53-489 4444; telefax +31 53-489 4442; e-mail a.spierenburg@basics.utwente.nl. For scientific queries, contact eucas@tn.utwente.nl. Information also available at the web site http://eucas.tn.utwente.nl/eucas/intro.htm.
*July 14 - 16, 1997: Symposium on Synthesis, Properties and Applications of High Temperature Superconductors, Gold Coast, Queensland, Australia. Topics include (but are not limited to): powder synthesis and novel processing; chemistry, phase relationships, and nonstoichiometry; relationships between microstructures and properties; flux pinning and weak links; anisotropy and two-dimensional behavior; transport and magnetic properties; mechanical properties; processing for the development of flux pinning centers; fabrication of wires, tapes, magnets, and bulk materials; and applications and future trends. Abstracts (250 words) are solicited. Abstract deadline, January 5, 1997. Contact T. Chandra, Department of Materials Engineering, University of Wollongong, Wollongong 2522, Australia; telefax +61 42 213-112 or -214-921; e-mail t.chandra@uow.edu.au.
July 27 - Aug. 1, 1997: International Conference on Magnetism (ICM '97), Cairns Convention Center, Cairns, Australia. Includes Symposium on Strongly Correlated Electron Systems. Designed to survey the developments in the field of magnetism in the previous three years. Format consists of plenary lectures, workshops, lecture sessions, and posters. Abstract deadline, January 17, 1997. Proceedings to be published in J. Magnetism and Mag. Mater. For information, contact the International Conference on Magnetism, 108 Church Street, Hawthorn Victoria, Australia 3122; telephone +61 3 9819 3700; telefax +61 3 9819 5978; e-mail icm@meetingplanners.com.au.
*Aug. 25 - 28, 1997: 16th General Conference of the Condensed Matter Division of the European Physical Society, Katholieke Universiteit Leuven, Leuven, Belgium. Particular emphasis on the following areas: low-temperature physics and superconductors, magnetism and metals, semiconductors and insulators, soft matter and statistical mechanics, and surfaces and interfaces. Special symposium "Forty Years of the Vortex State" by A. A. Abrikosov. For further information, contact The Secretary-General, 16th CMD-General Conference, Departement Natuurkunde K. U. Leuven, Celestijnenlaan 200 D, B-3001 Leuven, Belgium; telephone +32 16 32 71 75; telefax +32 16 32 79 83.
*Oct. 20 - 24, 1997: 15th International Conference on Magnet Technology (MT-15), Beijing, China. Purpose is to survey new techniques and developments in the fields of both superconducting and conventional magnets, and their operation and of application. Appropriate topics for the conference include: magnets for research; industrial applications of magnets; other application areas (biology, medicine, chemistry, etc.); materials for magnets (superconductors and their electrodynamics, structural and insulating materials, etc.); cryogenics; mechanical and electromagnetic calculation; basic magnet design and computation; instrumentation; measurement; and testing. Proceedings to be published in a special issue of IEEE Transaction on Magnets. Abstract deadline, April 30, 1997. For further information, contact Liangzhen Lin, Chair of MT-15 Program Committee, Applied Superconductivity Division, Institute of Electrical Engineering, Chinese Academy of Sciences, P.O.Box 2703, Beijing 100080, People's Republic of China; telephone +86 10-6256-1492; telefax +86 10-6256-0904; e-mail asd@piano.iee.ac.cn.
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Positions Available: Four fixed-term Research Fellow/Associate Fellow positions are available at the Center for Superconducting and Electronic Materials at the University of Wollongong, Australia. Projects include work involving HTS wire fabrication and characterization, HTS magnet design and construction and/or cryocooler design and construction, HTS irradiation and characterization, and critical current and flux pinning. Applicants must have experience in one or more of the above areas. Application deadline, January 10, 1997. For further information, contact S. X. Dou, Director, Center for Superconducting and Electronic Materials, University of Wollongong NSW 2522, Australia; telephone +61 42 21 4558; telefax +61 42 21 4577; e-mail shi_dou@uow.edu.au. To apply, submit four copies of application and names and addresses of three references to Personnel Officer, Confidential Appointment, University of Wollongong, NSW 2522, Wollongong, Australia; telefax +61 42 213 700; e-mail hutchingson@uow.edu.au; web site http://www.uow.edu.au.
Positions Open: A limited number of postdoctoral positions in condensed-matter theory are available at the International Centre for Theoretical Physics, Trieste, Italy, beginning fall 1997. Current research areas include strongly correlated electron systems, disordered and mesoscopic systems, ab-initio electronic structure studies, surface physics, statistical mechanics, and complex systems. Application deadline, December 31, 1996. Applications should be sent to Condensed Matter Secretary, International Centre for Theoretical Physics (ICTP), P.O. Box 586, I-34100 Trieste, ITALY; telephone +39 40 224241; telefax +39 40 224531.
High-Tc Update is the high-Tc superconductivity information exchange newsletter. Please send 1) preprints, reprints, and other research reports; 2) descriptions of on-going work; 3) meeting announcements and summaries.
The information contained herein is intended for limited distribution. Readers are expected to respect the rights of the authors.
Please address all contributions and inquiries to: Dr. Sreeparna Mitra, A219 Physics, Ames Laboratory/Iowa State University, Ames, Iowa 50011-3020. Telephone: (515) 294-3877. Telefax: (515) 294-1134. Telex: 269266. E-mail: MITRA@AMESLAB.GOV or MITRA@IASTATE.EDU. Project Director/Editor: Sreeparna Mitra Science Editor: John R. Clem High-Tc Update, Vol. 10, #24, December 15, 1996.