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: Happy Birthday to us! High-Tc Update has completed ten years of publication and begins its eleventh year with this issue. We take this opportunity to thank our MASTHEAD sponsors (agencies that provide funding of $15,000 or more per fiscal year) for their long-term enthusiastic support for the project. Our present MASTHEAD sponsors are BES/DOE, APRA, ONR, and NSF. Recent other sponsors have been NIST, EPRI, NASA and AFOSR. Thanks also to all our readers for your contributions (both scientific and financial) over the years! Please take a look at pages 14 and 15 for some interesting statistics collected for High-Tc Update over the years.

RBa2Cu3O7-d

CuO2-plane [17]^O NMR measurements in Ni-substituted YBa2Cu3O6+y are reported by J. Bobroff (Orsay) et al. The Ni moment induces an oscillatory spin density that broadens the NMR line. The authors thus were able to determine features of the spatially dependent magnetic susceptibility chi'(r) in the CuO2 planes and its temperature dependence.

Using the techniques of neutron diffraction, specific heat, magnetic susceptibility, and crystalline electric field spectroscopy, G. Boettger (ETH Zurich and PSI) et al. have found that Er2Ba4Cu7O14.92 (Tc = 89 K) exhibits three-dimensional antiferromagnetic ordering of the Er^[3+] ions below T_N = 0.54 K. In the ordered state, the propagation vector is k = (1/2,0,0), the Er ions are oriented parallel to the b axis, and there is a correlation length of about 130 Angstroms along the c axis.

A preprint by A. M. Hu (Jena and Beijing) et al. reports the preparation of Nd1+xBa2-xCu3O7-d bulk samples using a new melt-texturing process in air. The diameter of a single grain reached 1 cm, the Tc was 93 K, and 77 K Jc values were 2.4 x 10^4 A/cm^2 in zero field and 1.7 x 10^4 A/cm^2 in 1 T.

As explained by M. W. Klein and S. B. Simanovsky (Worcester Polytechnic), the observed decrease in Tc of YBa2Cu3O7-d with uniaxial pressure along the a direction and an approximately equal increase with pressure along the b direction near Tc ~~ 91.5 K (d ~~ 0) are in agreement with the authors' tunneling-unit model for high-Tc superconductivity. The corresponding jumps in the thermal expansion coefficients near Tc along the a and b directions also are in agreement with the theory. The authors propose further experiments to test the model for values of d in the range 0 <= d <= 0.5.

The properties of high-purity (>99.995%) YBa2Cu3O7-d crystals grown in BaZrO3 crucibles are reported by A. Erb et al. (Geneve). Such crystals have made possible the observation of (a) vortex-core structure by scanning tunneling microscopy (STM), (b) vortex-lattice melting by calorimetric measurements, (c) an absence of the Schottky anomaly in the low-temperature specific heat, and (d) a reversible suppression of the fishtail effect.

O K-edge and Cu L_[23]-edge x-ray-absorption near-edge structure (XANES) spectra in Dy1-xPrxBa2Cu3O7-d (0 <= x <=0.7) have been measured by J. M. Chen (SRRC) et al. to investigate how the variation of hole states is related to the superconductivity in these compounds. The O 2p hole concentrations in both the CuO2 planes and the CuO3 ribbons decrease monotonically with increasing Pr doping, as expected in the hole- depletion model of A. I. Liechtenstein and I. I. Mazin [Phys. Rev. Lett. 74, 1000 (1995)]. The authors conclude from these studies that the suppression of superconductivity with Pr doping results primarily from the hole-depletion effect.

Using oxide-melt drop-solution calorimetry, V. E. Lamberti (Princeton) et al. have performed extensive comparative thermochemical investigations of LnBa2Cu3O7-d (Ln = Pr, Nd, Eu, Gd, Dy, Ho, Tm), LnBa2Cu4O8 (Ln = Sm, Eu, Gd, Dy, Ho), and Y1-xPrxBa2Cu3O7-d. The authors report lattice parameters, unit-cell volumes, orthorhombic distortions, volumes of mixing, enthalpies of drop-solution, enthalpies of formation, and the superconducting critical temperatures.

Bi Cuprates

A preprint by G. Villard (Caen) et al. reports on the properties of single crystals of Bi2Sr2Ca1-xYxCu2O8+d grown by a self-flux method. Significantly enhanced values of Jc and irreversibility field, as well as the highest Tc, were obtained for x = 0.28.

Measurements of the resistivities of Bi2Sr2CaCu2O8+d (Bi-2212) crystals along both the ab plane and the c axis are reported by M. Chung et al. (Pohang). The authors find thermally activated behavior for both directions with almost the same activation energy, suggesting that the dissipation in the two directions has the same origin.

A softening of high-frequency phonon modes in Bi2Sr2Ca2Cu3O10+d (Bi- 2223) at high pressure has been found by V. M. Svistunov (Donetsk) et al. By measuring Andreev reflections in S-c-S microjunctions (S = superconductor, c = normal-state constriction) under pressures up to 10 kbar, the authors found that the oxygen breathing mode and the Cu-O bending mode both soften under pressure. The authors thus explain the observed rise in the ratio 2Delta/k_BTc under pressure in terms of a strong electron-phonon interaction model.

Grain-boundary weak links in Bi-2223 tapes are studied in a preprint by P. N. Mikheenko et al. (Wollongong). The authors report that at all temperatures higher than the Kosterlitz-Thouless transition temperature of an isolated superconducting layer, the critical current is determined entirely by the Josephson interaction between layers.

The local values of the critical transport current density Jc in Ag- sheathed (Bi,Pb)-2223 tapes containing silver addition of different particle sizes have been determined by Z. Yi (Southampton) et al. By successive removal of material, the authors found that the (77 K, self- field) Jc of tapes without silver addition and with 8 wt% silver addition of small particle size decreased continuously with distance from the superconductor-sheath interface; the Jc of layers close to the silver sheath was up to four times higher than that of superconducting material farthest from the interface. On the other hand, a tape with addition of 50 wt% 80 micrometers silver particles showed a uniform Jc of about 2 x 10^4 A/cm^2 throughout the superconducting core thickness.

The effect of bending on the current-carrying properties of (Bi,Pb)-2223 tapes has been studied by M. R. Koblischka et al. (Oslo) using magneto- optical visualization of magnetic flux distributions. The authors found that bending of the tape caused a series of cracks running perpendicular to the tape axis (or rolling direction). The flux penetration changed from nearly homogeneous for the as-prepared tape to entirely crack- governed for the bent tape.

Studies of the microstructure in superconducting Bi-2223 composite tapes are reported by M. Lahtinen (Tampere) et al. The authors found that crack propagation in well-textured Ag-sheathed tapes took place preferentially in the tape plane, whereas the cracks in tapes with less texture were oriented perpendicular to this plane.

A three-dimensional numerical analysis of transient distributions of temperature, critical current density, electrical resistance, and transport current in a superconducting Bi-2223/Ag tape under thermal disturbances is reported by H. Reiss (ABB). The author reports results for point-like or extended thermal disturbances of finite duration, accounting for the strongly anisotropic thermal conductivity. The results yield reliable maximum values of transport current for safely avoiding quenches.

Other Cuprates

The mid-infrared optical absorption in insulating single crystals of La2CuO4, Sr2CuO2Cl2, and Nd2CuO4 has been studied by J. D. Perkins (MIT and NREL) et al. In addition to explaining the measured absorption spectra, the authors address general questions regarding the electronic structure of the undoped host materials for the copper-oxide high-Tc superconductors and the optical excitations of 2D spin-1/2 antiferromagnets. In particular, the authors found that the lowest- energy crystal-field exciton likely has an energy of ~0.5 eV, much lower than generally believed.

The effect of sodium doping in the Hg-based cuprates has been studied by S. H. Yoo (Kansas) et al. The authors found that superconductivity can be achieved in samples containing 10% or less sodium. The resulting superconducting phase was found to have the same lattice structure and lattice constants as those of Hg-1223, but the normal-state resistivity behaved differently. The onset Tc was typically above 140 K, and the zero-resistance Tc was up to 135 K. The processing temperature was found to be at least 60^oC lower than that used for pure Hg-1223, which is advantageous for film fabrication.

Atomistic computer simulation techniques have been used by M. S. Islam et al. (Surrey) to investigate the defect properties of high-temperature superconductors. The calculated energies were found to be fully compatible with the observation that HgBa2CuO4+d (Hg-1201) is rendered superconducting by oxygen incorporation at interstitial sites, while Ca2CuO2Cl2 exhibits superconductivity only when doped with alkali metal ions (e.g., Na^+ and K^+).

A high-pressure experiment by C. Looney (Washington University) et al. has revealed evidence for oxygen-defect relaxation at temperatures as low as 13 K in Tl2Ba2CuO6+d (Tl-2201). A tiny (~1 microgram) sample was placed in a diamond-anvil cell loaded with dense helium and subjected to ~6 GPa hydrostatic pressure, which drove the superconducting transition temperature Tc down from 40 K to ~9 K.

A preprint by V. Hardy et al. (Caen) reports measurements of the in- and out-of-plane resistivities rho_[ab] and rho_c in single crystals of Tl2Ba2CaCu2O8+d (Tl-2212) and Tl2/3Bi1/3Ba2Ca1Cu2O7 [(Tl,Bi)-1212]. The rho_c values were found to be much lower in Tl-monolayer (Tl,Bi)-1212 than in Tl-bilayer Tl-1212. The authors used these measurements to test predictions by D. H. Kim et al. [Physica C 177, 431 (1991)] about the influence of the blocking-layer thickness on rho_c and the irreversibility line.

Vortices

A series of avalanche-like jumps has been observed by A. P. Hope (SUNY- Buffalo) et al. in the mixed state of single-crystal YBa2Cu3O7-d. A saw-tooth pattern in torque versus field orientation was found over a restricted range of angles. The authors explain the jumps in terms of a collaboration between twin-boundary pinning and the layered nature of the materials, which promotes a crossover from a tilted to a kinked vortex structure.

The equilibrium magnetization for layered superconducting films in a magnetic field H_|| applied parallel to the layers has been computed by J. P. Rodriguez (Madrid and Cal State-Los Angeles) in the vicinity of the decoupling transition. The author finds an anomalous H_||^[-1] tail at high fields. A collective pinning effect is also identified for c- axis transport limited by a single twin boundary oriented parallel to H_||.

Measurements of a dynamically induced instability in the vortex state of an amorphous multilayer and a single alloy layer of Ta/Ge are reported by R. J. Ruck (Wellington) et al. The experiments are in quantitative agreement with a theory by A. I. Larkin and Yu. N. Ovchinnikov [Zh. Eksp. Teor. Fiz. 31, 1915 (1975) or Sov. Phys. JETP 41, 960 (1976)], who calculated a critical vortex velocity at which the vortex viscous drag reaches a peak and an instability occurs.

Thin Films

Exceptional room-temperature transport properties in new Bi-Sr-Ca-Cu-O compounds synthesized by sequentially imposed layer epitaxy are reported in a preprint by M. Lagues (Paris) et al. The Cu/Ca ratio in these compounds is typically twice the value for conventional Bi2Sr2Can- 1CunO2n+4, and the new compounds are also Bi-deficient. The authors report that the room-temperature electrical resistivity of these compounds reaches extremely low values, orders of magnitude below that of copper. The authors also report strongly nonlinear I(V) characteristics of various forms, including cases where the voltage dependence at the onset of measurable dissipation is either exponential or parabolic as a function of current. The authors also present examples where I(V) exhibits a hysteretic behavior.

Measurements of the conductivity versus temperature and magnetic field in deoxygenated YBa2Cu3O7-d thin films are reported by K. Moloni et al. (Purdue). Field-independent exponents nu_g ~~ 1.9 and z_g ~~ 4.0 describe the glass transition at T_g(H) for 0 < H <= 26 T. At low fields, 3D XY exponents nu_[XY] ~~ 0.63 and z_[XY] ~~ 1.25 also are observed, with z_[XY] smaller than expected. These compete with glass scaling according to multicritical theory. A predicted power-law form of T_g(H) was observed for 0.5 Tc < T_g < Tc. For T_g < 0.5 Tc, 3D XY scaling fails, but a lowest-Landau-level analysis becomes possible.

As reported by M. Konishi et al. (SRL-ISTEC), YBCO films have been deposited on (100) YBCO single-crystal substrates using an off-axis rf magnetron sputtering method. At a substrate temperature of 580^oC, cracks formed because of cleavage properties and the large thermal stress at the tetragonal-orthorhombic transition. Such cracks would be fatal for electronics applications. At 760^oC, however, progress of the cracks is suppressed, and the films cover the cracks.

A paper by J. Ayache (Orsay) et al. reports studies of thin-film YBa2Cu3O7-d bicrystals using AFM, SEM, TEM, and HRTEM to characterize both the SrTiO3 substrate and the YBCO. The authors studied film-growth properties that affect zigzagging of the grain boundary.

Studies of the intrinsic Josephson effect along the c direction in high- temperature superconducting BSCCO and TBCCO mesa structures are reported by P. Seidel (Jena) et al. The authors observed dependencies of the critical current on both the external magnetic field and the microwave field.

Far-infrared transmission measurements have been used by X. Gerbaux (Nancy) et al. to determine the London penetration depth in thin films of YBa2Cu3O7-d and NbN.

Epitaxial superconducting thin films of Tl2Ba2CuO6+d (Tl-2201) with a continuous range of doping levels have been prepared by Z. F. Ren (SUNY- Buffalo) et al. using rf magnetron sputtering and two-step post- deposition annealing. Above Tc, the curves of normal-state resistance versus temperature showed negative curvature for underdoped films and positive curvature for overdoped films.

The effects of ion milling on the surface crystallinity of LaAlO3, SrTiO3, and NdGaO3, which are used as substrates in the fabrication of high-Tc Josephson junctions and circuits, have been studied by I. Takeuchi et al. (Maryland) using ion channeling and atomic force microscopy. The authors found that ion milling produces a disordered surface layer of thickness ~~60 Angstroms. Annealing the substrates in oxygen ambient at various temperatures ranging from 600^oC to 1100^oC, however, resulted in regrowth of the damaged layer.

Applications

A design study for a 5.6 MWh SMES (superconducting magnetic energy storage) unit needed for a MAGLEV power supply system in Japan has been carried out by S. Akita (CRIEPI) et al. The study assumes future availability of YBCO tapes with a critical current density of 5 x 10^4 A/cm^2 at 77 K and 8 T. An important advantage of operation at 77 K is that the refrigeration penalty is only around 20, as opposed to a value of around 500 at 4.4 K.

Theory

As reported by V. J. Emery (Brookhaven) et al., mobile holes in an antiferromagnetic insulator form a slowly fluctuating array of quasi- one-dimensional metallic stripes, which induce a spin gap or pseudogap in the intervening Mott-insulating regions. 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. This process is the analog of pairing in conventional superconductors. At nonvanishing stripe densities, Josephson coupling between stripes produces a dimensional crossover to a state with long-range superconducting phase coherence. In contrast to conventional superconductors, the superconducting state is characterized by a high density of (spin) pairs, but the phase stiffness, which is determined by the density and mobility of holes on the stripes, is very low.

A generalization of the Abrikosov-Gor'kov equations for nonmagnetic impurities in unconventional superconductors is proposed by S. Haas (ETH-Zurich) et al., who include higher harmonics in the expansion of the momentum-dependent gap function and a momentum-dependent impurity scattering potential. The model is treated within a self-consistent calculation to obtain the electronic density of states, the optical conductivity, and the gap function in a two-dimensional d_[x^2-y^2]-wave superconductor. The authors argue that momentum-dependent scattering from the impurities may lead to extended gapless regions in the gap function, centered around the nodes of the pure d_[x^2-y^2]-wave superconductor. The associated enhancement of the residual density of states may be responsible for the rapid decrease of Tc and the increase of the London penetration depth with hole doping observed in overdoped cuprate superconductors.

As shown by T. Emig (Koeln) et al., the surfaces of high-temperature superconductors are covered by dipole layers, where the charge-density modulation is induced by the local suppression of the gap function at the surface. The authors determine the structure of the surface dipole layer using a Ginzburg-Landau theory derived from the Gor'kov equations for d-wave pairing symmetry. The authors also discuss the contribution of this charging to the lens effect in superconducting films with holes, which was reported recently by C. Kriebel et al. [Ann. d. Phys. 4, 136 (1995)].

The dependence of the upper critical field upon temperature within the framework of the extended saddle-point model has been calculated by A. A. Abrikosov (Argonne). The author also discusses the discrepancies between theory and experiment.

The 3D XY scaling theory of superconductivity at zero and nonzero magnetic fields, based only upon the scaling hypothesis B ~ xi^[-2], has been developed by M. Friesen and P. Muzikar (Purdue). At high fields, or for temperatures far from the superconducting transition Tc, an outer scaling regime is predicted, for which the fields B, H, and H_[ex] all scale in a similar manner. Closer to the zero-field transition, an inner scaling region is found, for which the distinction between the different fields becomes essential; this represents the absolute 3D XY scaling behavior.

In the problem of depinning of periodic structures, such as charge density waves (CDW), vortex and domain-wall lattices, and Wigner crystals under an external driving force, all these systems share the property that there are many elastically coupled degrees of freedom interacting with a quenched random environment. V. M. Vinokur (Argonne) and T. Nattermann (Koeln) have studied charge density waves as a prototype system and found that depinning from strong disorder occurs via a two-stage process: The pinned system first experiences a continuous transition into a plastically sliding state and then undergoes a second sharp hysteretic transition into a coherently moving 3D state at higher drives.

Other Activities

Temperature-dependent anisotropy in the upper critical field H_[c2] of LuNi2B2C has been determined by V. Metlushko (Argonne) et al. from the temperature dependence of the magnetization. The authors found that H_[c2](T) had an upward curvature for all field directions, the in-plane anisotropy H_[c2]^<100>/H_[c2]^<110> decreased from 1.1 at 4.5 K to 1.0 at Tc = 16 K, and the average out-of-plane anisotropy (H_[c2]^<100> + H_[c2]^<110>)/2H_[c2]^<001> was essentially temperature-independent with a value of 1.16. All these effects can be described quantitatively in terms of a nonlocal extension of the Ginzburg-Landau theory, and the Fermi velocity averages determined from experiment are in good agreement with those obtained from recent band-structure calculations.

Using the classical theory of electrodynamics, Z. J. Yang (Argonne) shows how superconductors could be used to produce electron beams with transverse and longitudinal polarizations. The author notes that the results can in principle be used with beams of positrons or other particles with magnetic moments without major modifications.

A preprint by T. Shibauchi (Tokyo) et al. reports magnetic-field- dependent features in the microwave surface resistance indicative of the Josephson plasma resonance in the organic layered superconductor kappa- (BEDT-TTF)2Cu(NCS)2. In contrast to the behavior in Bi2Sr2CaCu2O8+d (Bi-2212), however, the interlayer phase correlation increases as the temperature is lowered below the irreversibility line.

The crystal structure of the composite crystal Ca13.6Sr0.4Cu24+yO41+z (y = -0.017 and z = -0.035) has been determined by T. Ohta (NIRIM) et al. This oxide comprises two interpenetrating subsystems: (a) [(Ca,Sr)2Cu2O3]_[infinite]containing alkaline-earth metals and spin-1/2 Heisenberg two-leg ladders and (b) one-dimensional [CuO2]_[infinite] chains of CuO4 squares sharing two opposite edges. The most remarkable structural feature is that Cu(1) atoms on the ladder are coordinated with O(3) atoms on neighboring [CuO2]_[infinite] chains to form CuO5 tetragonal pyramids locally. The Cu(1) atoms in the CuO5 pyramids have shorter equatorial Cu(1)-O bonds than those in CuO4 squares, providing evidence for hole doping into the five-coordinated Cu(1) atoms.

A preprint by M. Lagues (Paris) et al. reports transport properties of the h = 3 members of the MBE-grown cuprate spin ladders with the formula (Sr,Ca)h-1Cuh+1O2h. The room-temperature resistivity ranges from 1 milliohm-cm for Ca2Cu4O6 to 1 ohm-cm for Sr2Cu4O6. A superconducting transition at 40 K was observed in a sample with composition Bi4Sr4Ca3Cu10Oy, which may contain two-leg spin ladders. The presence of such ladders, however, remains to be confirmed by HRTEM.

Overviews

An overview by U. Balachandran (Argonne) reports recent progress under the DOE-supported applied superconductivity program entitled "Superconductivity Program for Electric Power Systems." Research is conducted in three categories: (a) wire development, (b) systems technology development, and (c) Superconductivity Partnership Initiative (SPI). The wire development activities are devoted to improving the critical current density Jc of short-length high-temperature superconducting wire, while activities in systems technology development focus on fabrication of long-length wires, coils, and magnets. SPI activities focus on the development of prototypes including a generator coil, a fault-current limiter, a transmission cable, and a motor (48 refs.).

A brief review of recent results on the ac losses in Ag-sheathed (Bi,Pb)-2223 tapes has been prepared by Y. Yang et al. (Southampton), focusing on (a) self-field losses in a variety of situations and (b) external-field losses with and without a dc transport current. The authors find good agreement between thermometric and electric loss measurements. The authors also discuss an ac-loss method that can be used to determine how the local Jc varies across the width of a tape (14 refs.).

Contributed by John R. Clem

Contents: Preprints begin on page 5; Coming Events begin on page 11; Resources are on page 13; HTCU statistics are shown on pages 14 and 15.

(Figures are not available in this ASCII version. Please see HTCU statistics at our Web site or view one of the coded versions.)

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.

R. Abd-Shukor, Baharudin Yatim, and S. L. Lau, "Formation of Tl-1212 Phase in (Tl0.8M0.2)Sr2(Ca,Cr)Cu2O7 (M=Cd and Sc) High-Tc Superconductor." To be published in J. Mater. Sci. Lett. Department of Physics, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan, MALAYSIA; telephone +60 3 8292904; telefax +60 3 8292880; e-mail ras@pkrisc.cc.ukm.my. Key words: electrical resistance, substitution effects, synthesis of (Tl0.8M0.2)Sr2(Ca1-xCrx)Cu2O7 (M=Cd and Sc) superconductors.

A. A. Abrikosov, "The Upper Critical Field in the Extended Saddle Point Model." Contact Janice Coble, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439; telefax (708) 252-9595; e-mail janice_coble@qmgate.anl.gov. 74.20.Mn; 74.20.Fg; 74.20.Hi; 74.25.Dw.

Shirabe Akita, Yoshihiro Wachi, Shinichiro Meguro, Takashi Saito, Kazuhiro Ueshiro, Kazuhiko Nishida, and Takakazu Shintomi, "Design Study of High-Tc SMES." Submitted to the Proc. of the 9th Int. Symp. on Supercond. (ISS'96), Sapporo, Hokkaido, Japan, Oct. 21-24, 1996. Central Research Institute of Electric Power Industry (CRIEPI), 2-11-1 Iwadokita, Komae-shi, Tokyo 201, JAPAN. Key words: SMES, High Tc superconductor, MAGLEV, ac loss.

V.P.S. Awana, Rajvir Singh, D. A. Landinez Tellez, J. M. Ferriera, J. Albino Aguiar, and A. V. Narlikar, "Structure Superconductivity and Normal State Magnetism of CaLaBaCu3-xFexO7 Superconductor, 0.0<=x<=0.24." To be published in Physica C (in press). Centre for Superconducting & Electronic Materials, University of Wollongong, Wollongong, NSW 2522, AUSTRALIA; telefax +61 42 21 3112; e-mail awana@uow.edu.au.

J. Ayache, A. Thorel, J. Le Duigou, J. Bonevich, and U. Dahmen, "Influence of the Growth Mechanism of the Grain Boundary Structure in YBa2Cu3O7 Thin Film Bicrystals." To be published in J. Alloys and Compounds: Proc. of the E-MRS Spring Mtg., Strasbourg, France, June 4- 7, 1996. CSNSM-IN2P3, CNRS, Batiment 108, F-91405 Orsay Campus, FRANCE; telephone +33 1 69 15 5219; telefax +33 1 69 15 5268; e-mail ayache@csnsm.in2p3.fr.

U. Balachandran, "Development of Ceramic Superconductors for Electric Power Applications." Submitted to the Proc. of the Int. Workshop on High-Temp. Supercond.: Ten Years After its Discovery, Jaipur, India, Dec. 16-21, 1996. Contact Janice Coble, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439; telefax (708) 252-9595; e- mail janice_coble@qmgate.anl.gov.

J. Bobroff, H. Alloul, Y. Yoshinari, A. Keren, P. Mendels, N. Blanchard, G. Collin, and J.-F. Marucco, "Using Ni Substitution and [17]^O NMR to Probe the Susceptibility chi'(q) in Cuprates." Submitted to Phys. Rev. Lett. Laboratoire de Physique des Solides, Universite Paris Sud, Batiment 510, F-91405 Orsay Cedex, FRANCE; e-mail bobroff@lps.u-psud.fr.

G. Boettger, P. Fischer, A. Doenni, P. Berastegui, Y. Aoki, H. Sato, and F. Fauth, "Long-Range Magnetic Order of the Er Ions in Er2Ba4Cu7O14.92." To be published in Phys. Rev. B (in press). Laboratory for Neutron Scattering, Eidgenoessische Technische Hochschule Zurich and Paul Scherrer Institut, Bldg. WHGA/131, CH-5232 Villigen PSI, SWITZERLAND; telephone +41 56 310 4374; telefax +41 56 310 2939; e-mail grit.boettger@psi.ch. 74.72.Jt; 75.25.+z; 61.72.Nn.

J. M. Chen, R. S. Liu, J. G. Lin, C. Y. Huang, and J. C. Ho, "Origin of Superconductivity Suppression in (Dy1-xPrx)Ba2Cu3O7 Studied by Soft X- Ray Absorption Spectroscopy." To be published in Phys. Rev. B (in press). Synchrotron Radiation Research Center, No. 1 R&D Road VI, Hsinchu Science-Based Industrial Park, Hsinchu 30077, Taiwan, REPUBLIC OF CHINA; telephone +886 35 78-0281; telefax +886 35 78-3892, -1881, or -3890; e-mail jmchen@alpha2.srrc.gov.tw or ktlu@alpha1.srrc.gov.tw. 74.25.Gz.

Moonkyo Chung, Hyun-Sik Chang, Yong Joo Doh, and Hu-Jong Lee, "The c- Axis Dissipation and Vortex Phases in Bi2Sr2CaCu2O8-x Single Crystals." Submitted to Phys. Rev. B. Contact Hu-Jong Lee, Department of Physics, Pohang University of Science and Technology, Pohang 790-784, KOREA; telefax +82 562 279 3099; e-mail hjlee@vision.postech.ac.kr. 74.50.+r; 74.60.Ge; 74.72.Hs; 74.25.Fy; 74.25.Dw.

H. Deng, C. Dong, J. C. Shen, F. Wu, H. Chen, S. L. Jia, G. C. Che, and Z. X. Zhao, "The Effects of Sulphur Substitution on Y(Ba,Sr)2Cu2.5B0.5Oz Systems." To be published in Physica C (in press). Contact C. Dong, National Laboratory for Superconductivity, Institute of Physics, Academia Sinica, Beijing 100080, PEOPLE'S REPUBLIC OF CHINA. Key words: sulphur, substitution effects, Y(Ba,Sr)2Cu2.5B0.5Oz, superconductivity.

V. J. Emery, S. A. Kivelson, and O. Zachar, "Pairing and Phase Coherence in High Temperature Superconductors." Presented at the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Department of Physics, Brookhaven National Laboratory, Upton, NY 11973.

Thorsten Emig, Kirill Samokhin, and Stefan Scheidl, "Charge Modulation at the Surface of High-Tc Superconductors." Institut fuer Theoretische Physik, Universitaet zu Koeln, Zuelpicher Str. 77, D-50937 Koeln, GERMANY; e-mail te@thp.uni-koeln.de; preprint also available at cond- mat@xxx.lanl.gov (#9702161). 73.30.+y; 74.50.+r; 61.16.Bg.

Andreas Erb, Jean-Yves Genoud, Marc Dhalle, Eric Walker, and Rene Fluekiger, "Reversible Suppression of the So-Called Fishtail Effect in Ultra Pure Single Crystals of YBa2Cu3O7-d." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Departement de Physique de la Matiere Condensee, Universite de Geneve, 24 quai Ernest-Ansermet, CH-1211 Geneve 4, SWITZERLAND; telephone +41 22 702-6234 or -6228; telefax +41 22 702- 6869; e-mail erb@sc2a.unige.ch. Key words: fishtail effect, critical currents, single crystals.

Andreas Erb, Eric Walker, Jean-Yves Genoud, and Rene Fluekiger, "Improvements in Crystal Growth and Crystal Homogeneity and Its Impact on Physics." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Departement de Physique de la Matiere Condensee, Universite de Geneve, 24 quai Ernest-Ansermet, CH-1211 Geneve 4, SWITZERLAND; telephone +41 22 702-6234 or -6228; telefax +41 22 702-6869; e-mail erb@sc2a.unige.ch.

Andreas Erb, Eric Walker, Jean-Yves Genoud, and Rene Fluekiger, "10 Years of Crystal Growth of the 123- and 124-High-Tc Superconductors: From Al2O3 to BaZrO3: Progress in Crystal Growth and Sample Quality and Its Impact on Physics." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Departement de Physique de la Matiere Condensee, Universite de Geneve, 24 quai Ernest-Ansermet, CH-1211 Geneve 4, SWITZERLAND; telephone +41 22 702-6234 or -6228; telefax +41 22 702-6869; e-mail erb@sc2a.unige.ch. Key words: crystal growth, impurities, BaZrO3.

Mark Friesen and Paul Muzikar, "3D XY Scaling Theory of the Superconducting Phase Transition." Submitted to Phys. Rev. B. Department of Physics, 1396 Physics Bldg., Purdue University, West Lafayette, IN 47907-1396; telephone (317) 494-3045; telefax (317) 494- 0706; e-mail friesen@physics.purdue.edu; preprint also available at cond-mat@xxx.lanl.gov (#9703135). 74.40.+k; 74.25.Bt; 74.25.Dw.

J.-Y. Genoud, A. Erb, B. Revaz, and A. Junod, "Growth of High Purity YBa2Cu4Od and Y3Ba4Cu7O15-d Single Crystals in BaZrO3 Crucibles Under High Oxygen Pressure, and Absence of Magnetic "Fishtail" Effect." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Industrial Research Limited, P.O. Box 31310, Lower Hutt, New Zealand; A. Erb's telephone (in Switzerland) +41 22 702-6234 or -6228; telefax +41 22 702-6869; e-mail erb@sc2a.unige.ch.

Xavier Gerbaux, M. Tazawa and Aarmand Hadni, "Far IR Study of the London Penetration Depth from 5 K to 70 K in a Very Thin Film of YBa2Cu3O7-d: Comparison with NbN, a One Gap Superconductor." To be published in C. R. Acad. Sci. Laboratoire de Cristallographie et Modelisation des Materiaux Mineraux et Biologiques, URA-CNRS, No. 809, Universite Henri- Poincare-Nancy 1, B.P. 239, F-54506 Vandoeuvre-les-Nancy Cedex, FRANCE; telephone +33 83 91-2271, -2013, or -2000; A. Hadni's telefax +33 83 85 4848.

N. V. Golyshev, Ya. S. Greenberg, S. F. Klimenko, and S. V. Motorin, "The Software for the Calculation of the Output Signal and Noise Characteristics of SQUID Readout Electronics." Submitted to the 6th Int. Supercond. Electronics Conf. (ISEC'97), Berlin, Germany, June 26 - 28, 1997. Novosibirsk State Technical University, 20 K. Marx Ave., 630092 Novosibirsk, RUSSIA; Ya. S. Greenberg's telefax +7 383 246 0209; e-mail grinberg@redhouse.nstu.nsk.su.

N. V. Golyshev, Ya. S. Greenberg, and S. V. Motorin, "The Choice of the Optimum Bandwidth of a Superconducting Magnetocardiograph." Submitted to the 6th Int. Supercond. Electronics Conf. (ISEC'97), Berlin, Germany, June 26 - 28, 1997. Novosibirsk State Technical University, 20 K. Marx Ave., 630092 Novosibirsk, RUSSIA; Ya. S. Greenberg's telefax +7 383 246 0209; e-mail grinberg@redhouse.nstu.nsk.su.

Stephan Haas, A. V. Balatsky, Manfred Sigrist, and T. M. Rice, "Extended Gapless Regions in Disordered d_[x^2-y^2]-Wave Superconductors." Submitted to Phys. Rev. Lett. Theoretical Physics, ETH-Hoenggerberg, CH-8093 Zurich, SWITZERLAND; telephone +41 1 6332575; telefax +41 1 6331115; e-mail haas@itp.ethz.ch.

N. M. Hamdan, A. S. Al-Harthi, and M. F. Choudhary, "Effect of gamma-- Irradiation on the Critical Current Density of Tl/F Superconductors." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran, 31261, SAUDI ARABIA; telephone +966 3 860 2255; telefax +966 3 860 2293; e-mail c-phys@dpc.kfupm.edu.sa.

V. Hardy, A. Maignan, C. Martin, F. Warmont and J. Provost, "Anisotropy of Resistivity in Tl-Based Single Crystals: Direct Evidence for the Influence of the Blocking Layers Thickness and Correlation with Superconducting Properties." To be published in Phys. Rev. B. Laboratoire CRISMAT, CNRS, URA 1318, ISMRA et Universite de Caen, 6 Boulevard du Marechal Juin, F-14050 Caen Cedex, FRANCE. 74.72.Fq; 74.25.Fy; 74.60.Ge.

A. P. Hope, M. J. Naughton, D. A. Gajewski, and M. B. Maple, "Flux Jump Avalanches in Torque Studies of Single Crystal YBa2Cu3O7." Submitted to Phys. Rev. Lett. Contact M. J. Naughton, Department of Physics, State University of New York, 239 Fronczak Hall, Buffalo, NY 14260-1500; telephone (716) 645-2019; telefax (716) 645-2507; e-mail naughton@ascu.buffalo.edu. 74.60.Ge; 74.25.Ld; 74.60.Ec.

M. Houssa, M. Ausloos, R. Cloots, and H. Bougrine, "Superconducting Fluctuations in the Thermal Conductivity of Bi2Cu2CaCu2O8 and DyBa2Cu3O7-x Materials." To be published in Phys. Rev. B. SUPRAS, Institute of Physics B5, University of Liege, B-4000 Liege, BELGIUM; telephone +32 41 66 3703; telefax +32 41 66 2990; e-mail houssa@gw.unipc.ulg.ac.be. 74.25.Fy; 74.40.+k; 74.72.Bk; 74.72.Hs.

A. M. Hu, Z. X. Zhao, M. Z. Wu, C. Wende, T. Strasser, B. Jung, G. Bruchlos, W. Gawalek, and P. Goernert, "Superconducting Properties of Melt Textured Nd1+xBa2-xCu3Oy Prepared in Air." To be published in Physica C. National Laboratory for Superconductivity, Institute of Physics, Chinese Academy of Sciences, Beijing 100080, PEOPLE'S REPUBLIC OF CHINA; telefax +86 10 256 8834; e-mail shx@aphy01.iphy.ac.cn. Key words: melt-textured materials, Nd1+xBa2-xCu3Oy, superconducting properties.

M. Saiful Islam, Mark S. D. Read, and Severine D'Arco, "From Oxides to Oxyhalides: Modelling the Properties of High Tc Superconductors." To be published in Faraday Discussion. Department of Chemistry, University of Surrey, Guildford GU2 5XH, UNITED KINGDOM; telephone +44 1483 300800, ext. 2596; telefax +44 1483 300803; e-mail m.islam@surrey.ac.uk.

A. Junod, M. Roulin, J.-Y. Genoud, B. Revaz, E. Walker, A. Erb, C. Marcenat, R. Calemczuk, and F. Bouquet, "Specific Heat Anomalies on the Vortex Melting Line in YBa2Cu3O7-d up to B=23 Teslas: Observation of First- and Second-Order Transitions, Effect of Oxygen Doping, Field Orientation, Crystal Purity and Detwinning." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Departement de Physique de la Matiere Condensee, Universite de Geneve, 24 quai Ernest-Ansermet, CH-1211 Geneve 4, SWITZERLAND; telephone +41 22 702-6204; telefax +41 22 702-6869; e- mail junod@sc2a.unige.ch.

A. Junod, M. Roulin, B. Revaz, A. Mirmelstein, Y.-J. Genoud, E. Walker, and A. Erb, "Specific Heat of High Temperature Superconductors in High Magnetic Fields." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S- HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Departement de Physique de la Matiere Condensee, Universite de Geneve, 24 quai Ernest-Ansermet, CH-1211 Geneve 4, SWITZERLAND; telephone +41 22 702-6204; telefax +41 22 702-6869; e-mail junod@sc2a.unige.ch.

Hirotake Kajii, Hisashi Araki, Anvar A. Zakhidov, Kazuya Tada, Kyuya Yakushi, and Katsumi Yoshino, "Microwave Heating Effect on Two Josephson-Junction Systems in Granular PAT12-C60-Rb Composites: Low- Field Microwave Absorption Study." To be published in Physica C (in press). Department of Electronic Engineering, Faculty of Engineering, Osaka University, Yamada-Oka, Suita, Osaka 565, JAPAN. Key words: conducting polymer, fullerene, low-field microwave absorption, superconducting.

B. W. Kang, W. N. Kang, S. H. Yun, and J. Z. Wu, "Scaling Behavior of Pinning Potential of HgBa2CaCu2O6+d Thin Films." Submitted to Phys. Rev. B. Department of Physics and Astronomy, University of Kansas, Lawrence, KS 66045; e-mail kang@kuphsx.phsx.ukans.edu.

Michael W. Klein and Sergey B. Simanovsky, "Anisotropic Pressure Dependence of Tc in YBa2Cu3O7-d: Evidence for the Tunneling-Unit Model." To be published in Phys. Rev. Lett. Department of Physics, Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609-2280; telephone (508) 831-5258; telefax (508) 831-5886; Web site http://www.wpi.edu/.

M. R. Koblischka, T. H. Johansen, and H. Bratsberg, "Bending of Silver- Sheathed (Bi,Pb)-2223 Tapes Investigated by Magneto-Optical Flux Visualization." Submitted to Supercond. Sci. Technol. Department of Physics, University of Oslo, P.O. Box 1048, Blindern, N-0316 Oslo 3, NORWAY; telefax +47 22 856422; e-mail m.r.koblischka@fys.uio.no. 74.60.Ec; 74.60.Ge; 74.60.Jg.

M. Konishi, J. G. Wen, Y. Matsunaga, Y. Enomoto, S. Koyama, and Y. Shiohara, "Homoepitaxial Growth of a-axis Oriented YBCO Thin Films on Single Crystals." To be published in J. Cryst. Growth. 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.

M. Lagues, J. Y. Laval, C. F. Beuran, C. Deville Cavellin, B. Eustache, J. B. Moussy, C. Partiot, and X. Z. Xu, "Transport Properties of MBE Grown Cuprate Spin Ladders." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M2S-HTSC V), Beijing, People's Republic of China, Feb. 28- Mar. 4, 1997. Laboratoire Surfaces et Supraconducteurs, Universite Paris 12, CNRS, UPR5, ESPCI, 10 rue Vauquelin, F-75231 Paris, FRANCE; telephone +33 1 4079-4625 or -4701; telefax +33 1 4079 4425; e-mail michel.lagues@espci.fr.

M. Lagues, C. Partiot, V. Mairet, C. Hatterer, X. Z. Xu, and C. Deville Cavellin, "Room Temperature Transport Properties of New BiSrCaCuO Compounds." To be published in Comptes Rendus de l'Academie des Sciences (Paris). Laboratoire Surfaces et Supraconducteurs, Universite Paris 12, CNRS, UPR5, ESPCI, 10 rue Vauquelin, F-75231 Paris, FRANCE; telephone +33 1 4079-4625 or -4701; telefax +33 1 4079 4425; e-mail michel.lagues@espci.fr.

Markku Lahtinen, Jaakko Paasi, Zhenghe Han, and Jyrki Sarkaniemi, "Microstructure of the Ceramic in Superconducting Bi-2223 Composite Tapes after Bending Strain Cycles." To be published in Physica C (in press). Laboratory of Electricity and Magnetism, Tampere University of Technology, P.O. Box 692, FIN-33101 Tampere, FINLAND; telephone +358 3 365 2009; telefax +358 3 365 2160; e-mail ml73348@ee.tut.fi. Key words: Bi-2223 composite superconductor, bending strain, fracture. 74.80.-g; 74.72.Hs; 74.25.Ld; 62.20.Mk.

V. E. Lamberti, M. A. Rodriguez, J. D. Trybulski, A. Navrotsky, and H. B. Liu, "Thermochemical Studies of LnBa2Cu3O7-d (Ln=Pr,Nd,Eu,Gd,Dy,Ho,Tm), LnBa2Cu4O8 (Ln=Sm,Eu,Gd,Dy,Ho), and Y1- xPrxBa2Cu3O7-d." To be published in Chemistry of Metals. Contact A. Navrotsky, Department of Chemical Engineering and Materials Science, University of California at Davis, Davis, CA 95616; e-mail anavrotsky@ucdavis.edu.

C. Looney, J. S. Schilling, S. Doyle, and A. M. Hermann, "Evidence for Oxygen Relaxation Below 15 K in Superconducting Tl2Ba2CuO6+x." Submitted to Physica C. Department of Physics, Washington University, C.B. 1105, One Brookings Drive, St. Louis, MO 63130.

C. Marcenat, R. Calemczuk, A. Erb, E. Walker, and A. Junod, "Observation of the Vortex Melting Line in YBa2Cu3O7 by Specific Heat Measurements in Very High Magnetic Field: H <= 23 Tesla." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Departement de Recherche Fondamentale sur la Matiere Condensee, SPSMS/LCP, CEA/Grenoble, 17 rue des Martyrs, F-38054 Grenoble Cedex 9, FRANCE; A. Erb's telephone +41 22 702-6234 or -6228; telefax +41 22 702-6869; e-mail erb@sc2a.unige.ch.

A. P. Menushenkov, S. Benazeth, J. Purans, A. Yu. Ignatov, and K. V. Klementev, "Local Structure Anomalies of the BaBi(Pb)O3 System at Low Temperatures: An X-ray Absorption Study." To be published in Physica C (in press). Moscow Engineering Physics Institute, 115409 Moscow, RUSSIA; telephone +7 95 323 9020; telefax +7 95 324 2111; e-mail menushen@htsc.mephi.ru. Key words: EXAFS, BPB, thermal fluctuation, low temperature.

V. Metlushko, U. Welp, A. Koshelev, I. Aronson, G. W. Crabtree, and P. C. Canfield, "Anistropic Upper Critical Field of LuNi2B2C." Submitted to Phys. Rev. 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.

P. N. Mikheenko, J. Horvat, Q. Y. Hu, M. Ionescu, and S. X. Dou, "Grain- Boundary Links and Critical Current of Bi2Sr2Ca2Cu3Ox/Ag Tapes." To be published in Supercond. Sci. Technol. Centre for Superconducting & Electronic Materials, University of Wollongong, Northfields Avenue, Wollongong, NSW 2522, AUSTRALIA; telephone +61 42 21 5726; telefax +61 42 21 5731; e-mail mikhe@uow.edu.au. 74.60.Jg; 74.80.Dm.

*Katerina Moloni, Mark Friesen, Shi Li, Victor Souw, P. Metcalf, Lifang Hou, and M. McElfresh, "3D XY and Lowest Landau Level Fluctuations in Deoxygenated YBa2Cu3O7-d Thin Films." To be published in Phys. Rev. Lett. Department of Physics, 1396 Physics Bldg., Purdue University, West Lafayette, IN 47907-1396; Mark Friesen's telephone (317) 494-3045; telefax (317) 494-0706; e-mail friesen@physics.purdue.edu; preprint also available at cond-mat@xxx.lanl.gov (#9703126). 74.25.Bt; 74.25.Dw; 74.72.-h. *Revised manuscript.

Tomoko Ohta, Fujio Izumi, Mitsuko Onoda, Masaaki Isobe, Eiji Takayama- Muromachi, and Alan W. Hewat, "Modulated Structure of the Composite Crystal Ca13.6Sr0.4Cu24+yO41+z." Submitted to J. Phys. Soc. Jpn. Contact Fujio Izumi, National Institute for Research in Inorganic Materials, 1-1 Namiki, Tsukuba, Ibaraki 305, JAPAN; e-mail izumi@nirim.go.jp. Key words: two-leg ladder, superconductor, superspace group, neutron diffraction, x-ray diffraction, Rietveld refinement.

J. D. Perkins, R. J. Birgeneau, J. M. Graybeal, M. A. Kastner, and D. S. Kleinberg, "Mid-Infrared Optical Excitations in Undoped Lamellar Copper Oxides." Submitted to Phys. Rev. B. SERF/E100-49, National Renewable Energy Laboratory, 1617 Cole Boulevard, Golden, CO 80401-3393; telephone (303) 384-6606; telefax (303) 384-6655; e-mail jperkins@nrel.gov. 74.25.Gz; 74.72.-h; 75.30.Ds; 75.50.Ee; 78.30.Hv.

A. A. Pramana DN., Kh. A. Ziq, and N. M. Hamdan, "Magnetic Energy Loss in Polycrystalline YBa2Cu3O7-d with Varying Oxygen Content." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Department of Physics, King Fahd University of Petroleum and Minerals, Dhahran 31261, SAUDI ARABIA; N. M. Hamdan's telephone +966 3 860 2255; telefax +966 3 860 2293; e- mail c-phys@dpc.kfupm.edu.sa.

A. Rakitin, M. Kobayashi, and A. P. Litvinchuk, "Local Lattice Instability and Ionic Transport in High-Temperature Superconductors." Department of Physics, Niigata University, 950-21 Niigata, JAPAN. 64.70.Kb; 63.20.Kr; 66.30.Dn; 74.72.Bk; 74.25.Bt.

S. Ramanathan, Z. Li, and K. Ravi-Chandar, "On the Growth of BSCCO Whiskers." Preprint #97:030; to be published in Physica C. Texas Center for Superconductivity and Department of Mechanical Engineering, University of Houston, Houston, TX 77204-4792; telephone (713) 743-8200; telefax (713) 743-8201; e-mail preprints@www.tcs.uh.edu. Key words: high-temperature superconductors, whiskers, phase formation.

Harald Reiss, "Simulation of Thermal Conduction and Boiling Heat Transfer and Their Impact on the Stability of High Temperature Superconductors." To be published in the Proc. of the 14th. European Conf. Thermophys. Properties, Lyon, France, Sept. 16-19, 1996. Asea Brown Boveri Corporate Research Center Heidelberg, Speyerer Str. 4, D- 69115 Heidelberg, FEDERAL REPUBLIC OF GERMANY; telephone +49 6221 59 6459; telefax +49 6221 59 6512.

Z. F. Ren, J. H. Wang, and D. J. Miller, "Continually Underdoped Tetragonal Superconducting Tl2Ba2CuO6+d Thin Films." Submitted to Appl. Phys. Lett. Materials Laboratory, Department of Chemistry and New York State Institute on Superconductivity, State University of New York, Buffalo, NY 14260-3000; e-mail zren@acsu.buffalo.edu.

C. Rial, E. Moran, M. A. Alario-Franco, U. Amador, and N. H. Andersen, "Room Temperature Chemically Oxidized La2CuO4+y: Phase Separation Induced by Thermal Treatment." To be published in Physica C (in press). Contact U. Amador, Laboratory Difraccion Rayos-X, F. CC. Quimicas, Universidad Complutense, E-28040 Madrid, SPAIN. Key words: La2CuO4+y, phase separation, oxygen diffusion, superconductor, hole concentration, neutron diffraction, oxygen stoichiometry.

J. P. Rodriguez, "Critical Behavior of Layered Superconducting Films in Parallel Magnetic Field." Instituto de Ciencia de Materiales, Consejo Superior de Investigaciones Cientificas, Universidad Autonoma de Madrid, Cantoblanco, E-28049 Madrid, SPAIN. 74.20.De; 74.20.Mn; 74.60.Ge; 74.80.Dm.

Marlyse Roulin, Alain Junod, Eric Walker, and Andreas Erb, "High Resolution Specific Heat Experiments on the Melting Line of the Vortex Glass in YBa2Cu3Ox: Observation of Second-Order Transitions up to 14 Teslas." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Departement de Physique de la Matiere Condensee, Universite de Geneve, 24 quai Ernest-Ansermet, CH-1211 Geneve 4, SWITZERLAND; Alain Junod's telephone +41 22 702-6204; telefax +41 22 702-6869; e-mail junod@sc2a.unige.ch.

B. J. Ruck, J. C. Abele, H. J. Trodahl, S. A. Brown, and P. Lynam, "Vortex Dynamics and Instabilities in Layered and Homogeneous Ta/Ge Superconductors." To be published in Phys. Rev. Lett. Department of Physics, Victoria University of Wellington, P.O. Box 600, Wellington, NEW ZEALAND; telephone +64 4 471 5347; telefax +64 4 495 5237; e-mail ben.ruck@vuw.ac.nz. 74.25.Fy; 74.60.Ge; 74.80.Dm.

P. Seidel, A. Pfuch, U. Huebner, F. Schmidl, H. Schneidewind, T. Ecke, and J. Scherbel, "One-Dimensional Intrinsic Josephson Arrays Based on HTS Thin Films." To be published in Physica C: Proc. of the 1997 Int. Symp. on Intrinsic Josephson Effect and THz Plasma Oscillations in High- Tc Supercond., Sendai, Japan, Feb. 23-25, 1997. Institut fuer Festkoerperphysik, Friedrich-Schiller-Universitaet Jena, Lessingstrasse 8, D-07743 Jena, GERMANY; telephone +49 3641-635685 or -635681; telefax +49 3641-635681; e-mail seidel@ifk.uni-jena.de. Key words: BSCCO, TBCCO, thin film intrinsic Josephson junctions, subgap-structures.

P. Seidel, A. Plecenik, M. Grajcar, M. Belogolovskii, K.-U. Barholz, and A. Matthes, "Peculiarities of 'Tunneling' Characteristics Observed in HTS/Metal Point Contact Junctions." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High- Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Institut fuer Festkoerperphysik, Friedrich- Schiller-Universitaet Jena, Lessingstrasse 8, D-07743 Jena, GERMANY; telephone +49 3641-635685 or -635681; telefax +49 3641-635681; e-mail seidel@ifk.uni-jena.de.

F. Shi, R. Harris, W. J. Bresser, D. McDaniel, and P. Boolchand, "Metal (M) Dopant Centered Local Structures, High-Pressure Synthesis and Bulk Superconductivity in YBa2(Cu1-xMx)3O7-d: M=Fe,Co,Ni." To be published in J. Phys. Condens. Matter. Contact P. Boolchand, Department of Electrical, Computer Engineering, and Computer Science, University of Cincinnati, Cincinnati, OH 45221-0030; telephone (513) 556-4758 or -2836; telefax (513) 556-7326; e-mail pboolcha@ece.uc.edu.

T. Shibauchi, M. Sato, A. Mashio, T. Tamegai, H. Mori, S. Tajima, and S. Tanaka, "Josephson Plasma Resonance in the Mixed State of Organic Superconductor kappa-(BEDT-TTF)2Cu(NCS)2." To be published in Phys. Rev. B. Department of Applied Physics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113, JAPAN. 72.15.Qm; 72.15.Lh; 71.28.+d; 78.20.-e.

V. M. Svistunov, V. Yu. Tarenkov, A. I. D'yachenko, and R. Aoki, "Phonon Spectra in the Conductance of Andreev Junctions on Bi-2223 at High Pressure." To be published in Fizika Nizkikh Temperatur (Sov. Low Temp. Phys.) Galkin Physico-Technikal Institute, National Academy of Science of Ukraine, 72, R. Luxemburg St., 340114, Donetsk, UKRAINE; telephone +380 622 55-7562 or -7378; telefax +380 622 55-0127; e-mail svistuno@sts.dipt.donetsk.ua.

I. Takeuchi, R. P. Sharma, S. Choopun, C. J. Lobb, and T. Venkatesan, "Ion Milling Damage and Regrowth of Oxide Substrates Studied by Ion Channeling and Atomic Force Microscopy." To be published in Appl. Phys. Lett. Center for Superconductivity Research, Department of Physics, University of Maryland, College Park, MD 20742-4111; e-mail ichiro@ux8.lbl.gov.

T. Tatsuki, A. Tokiwa-Yamamoto, T. Tamura, S. Adachi, and K. Tanabe, "Annealing Study on (Hg,TI)2Ba2Can-1CunOy (n=1-5) Superconductors." To be published in Physica C. 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: Hg-TI-Ba- Ca-Cu-O, high-pressure synthesis, homologous series, superconductivity, post annealing.

G. Villard, D. Pelloquin, A. Maignan, and A. Wahl, "Growth and Superconductivity of Bi2Sr2Ca1-xYxCu2O8+d Single Crystals in the Tc Optimum Region." To be published in Physica C. Laboratoire CRISMAT, ISMRA et Universite de Caen, UMR 6508 associee au CNRS, 6 Boulevard du Marechal Juin, F-14050 Caen Cedex, FRANCE; telephone +33 2 31 45 2916; telefax +33 2 31 95 1600; e-mail physol@crismat.ismra.fr. 81.10.Fq; 61.66.-f; 74.60.Jg; 74.40.+k.

Valerii M. Vinokur and Thomas Nattermann, "Hysteretic Depinning of Anistropic CDW." To be published in Phys. Rev. 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. 61.20.Lc; 74.60.Ge; 74.60.Jg.

Rinke J. Wijngaarden, R. Surdeanu, R. Griessen, A. A. Menovsky, J. Fendrich, and W.-K. Kwok, "Measurement of Local Currents in Superconductors Using an In-Situ High Field Magneto-Optical Microscope." To be published in Physica C: Proc. of the 5th Int. Conf. on Mater. and Mech. of Supercond. -- High-Temp. Supercond. (M^2S-HTSC V), Beijing, People's Republic of China, Feb. 28-Mar. 4, 1997. Institute COMPAS and Faculty of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, THE NETHERLANDS.

Y. Yang, T. Hughes, and C. Beduz, "Characteristics of the ac Losses in Ag-Sheathed PbBi2223 Tapes." To be published in Cryogenics. Institute of Cryogenics, Southampton University, Southampton, UNITED KINGDOM.

Z. J. Yang, "Note on Polarizing Electron Beam." To be published in J. Supercond. Lucent Technologies, 2000 N. Naperville Road, Naperville, IL 60566; preprint also available from Janice Coble, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439; telefax (708) 252-9595; e-mail janice_coble@qmgate.anl.gov. Key words: electron and positron beam, superconductor, Meissner effect. 41.75.Fr; 41.60.Ap; 74.25.Ha; 41.90.+e.

Z. Yi, C. Beduz, M. Al-Mosawi, and R. Riddle, "Transverse Distribution of the Transport Current Density in (Bi,Pb)2223 Tapes." To be published in Physica C (in press). Department of Materials, Imperial College, Prince Consort Road, London, SW7 2BP, UNITED KINGDOM. Key words: (Bi,Pb)2223 tapes, critical current density distribution, V-I characteristics.

S. H. Yoo, J. Z. Wu, K. W. Wong, S. M. Wu, and W. Z. Zhou, "Superconductivity in Sodium-Doped Mercury-Based Cuprates." Department of Physics and Astronomy, University of Kansas, Lawrence, KS 66045; e- mail kimyoo@kuphsx.phsx.ukans.edu. Key words: high-temperature superconductivity, sodium, Hg-1223. 74.72.-h; 74.62.Bf.

S. L. Yuan, J. Zhou, Z. Huang, and N. F. Yao, "Scaling Approach to the In-Plane Resistivity of Single Crystalline La1.85Sr0.15CuO4 as a Function of Temperature, Magnetic Field and its Orientation." To be published in Physica C (in press). High Magnetic Field Laboratory, Advanced Institute of Hefei, Chinese Academy of Sinica, P.O. Box 1126, Hefei 230031, PEOPLE'S REPUBLIC OF CHINA. 74.60.Ge; 75.30.Gw; 74.80.Dm.

May 25 - 29, 1997: 11th International Colloquium on Plasma Processes (CIP'97), Le Mans Congress Hall, Le Mans, France. Organized by the French Vacuum Society. Colloquium will present recent process in research, applications, and developments of plasma surface interactions and plasma-assisted deposition of thin films. Conference intends to bring together basic researchers, engineers, and equipment manufacturers. Special topic on plasma cleaning. Equipment exhibition. For information, contact CIP'97, Palais des Congres, Rue d'Arcole, F- 72000 LeMans, France.

*June 15 - 18, 1997: Third Joint ISTEC/MRS International Workshop on Superconductivity: Suitable Materials and Processing for HTS Applications Towards the Next Decade, The Royal Waikoloan, Big Island, Hawaii. Will mainly be a single-session meeting with significant time allotted to encouraging the exchange of information among participants. Regular sessions titles are: processing of HTS bulk; processing of HTS wire, tapes, and thick films; crystal growth related to HTS processing of bulk and films; thin-film processing for rf applications; and fabrication and control of HTS junctions for digital circuits. Rump sessions: ac losses, vortex dynamics, and pinning; and SQUID and sensor applications. Invited and contributed oral presentations and posters. The workshop solicits HTS materials and products for an awards competition with suggested categories such as single crystals (largest volume, highest quality, etc.); thin films (largest area, smoothest surface, etc.); strong pinning specimens; wires and tapes; power leads; new products; and others. Early registration deadline, May 15, 1997. Contact Koji Kajimura, Electrotechnical Laboratory, 1-1-4 Umezono, Tsukuba, Ibaraki 305, Japan; telephone +81 298 54-5003; telefax +81 298 54-5070; e-mail kajimura@etl.go.jp or Eric Hellstrom, Department of Materials Science & Engineering, University of Wisconsin at Madison, Madison, WI 53706; telephone (608) 263-9462; telefax (608) 263-1087.

*June 30 - July 3, 1997: 3rd European Conference on Applied Superconductivity (EUCAS'97), Veldhoven, The Netherlands. Will include 9 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 and electronic applications, and large-scale and power applications. In addition, there will be special-topics presentations by invited lecturers on new materials, flux pinning, applied theory of superconductivity, packaging and cooling, and an overview of ISEC- Berlin. Participants can present work (mainly via poster sessions) related to the special topics after the special-topics lectures. 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.

Oct. 6 - 10, 1997: The Eighth Workshop on rf Superconductivity, Abano Terme (Padova), Italy. Workshop is planned as a forum for novel ideas and to provide channels of communication between accelerator scientists and industries concerned with advanced technologies. Papers from the whole field will be presented, including high-energy and heavy-ion machines as well as cyclotrons and FELs. Experience with resonators in existing superconducting accelerators will be reported. Will also cover future programs dealing with high-intensity structures that are of emerging interest to the community. Special section of the workshop to be dedicated to non-accelerator applications of rf superconductivity such as novel microwave devices (both low Tc and high Tc). Abstract deadline, June 13, 1997; early registration deadline, July 25, 1997. Proceedings to be published. Invited papers to be published as a special issue of Particle Accelerators. For information, contact A. Lombardi, The Eighth Workshop on rf Superconductivity, INFN LNL Via Romea 4, Legnaro (Padua) ITALY; telephone +39 49-8068 358; telefax +39 49-641925; e-mail alombardi@lnl.infn.it.

*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 applications. 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. 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.

*Jan. 6 - 9, 1998: 7th Joint MMM-Intermag Conference, San Francisco, Calif. Conference will include all basic and applied science technology related to magnetism. The technical subject categories are: cooperative phenomena and fundamental magnetic properties, transport properties, computational magnetics and imaging, soft magnetic materials and applications, hard magnetic materials and applications, other materials, artificially structured materials, magnetic recording, and interdisciplinary topics and applications. Invited talks, oral presentations, and poster sessions. Exhibition of services, equipment, and materials. Abstract deadline, July 9, 1997. Proceedings to be published in special issues of J. Appl. Phys. and IEEE Trans. on Mag. For further information, contact Diane Suiters or Amy Landsbaum, Conference Coordinators, 655-15th Street N.W., Suite 300, Washington, DC 20005; telephone (202) 639-5088; telefax (202) 347-6109; e-mail magnetism@courtesy.assoc.com. Technical questions regarding abstracts should be directed to one of the Program Chairs: Alison Chaiken, Mailstop L-350, Lawrence Livermore Laboratory, Livermore, CA 94550; telephone (510) 422-7129; telefax (510) 422-6892; e-mail chaiken@llnl.gov or Toasz Jagielinski, Eastman Kodak Company, 3985 Sorrento Valley Boulevard, San Diego, CA 92121; telephone (619) 535- 6908; telefax (619) 535-6990; e-mail tmj@kodaksdl.com.

*April 20 - 25, 1998: The Seventh Conference on Frontiers of Electron Microscopy in Materials Science, Kloster Irsee, Irsee, Germany. Purpose of this meeting is to establish the current state of the art of quantification of all relevant techniques used in electron microscopy including XEDS, EELS, Z-contrast, HREM, conventional TEM, CBED, and in- situ. Topical area: quantitative methods in electron microscopy. Number of participants limited to 100 (30 invited speakers, 20 invited session chairs, and 50 participants). For information, contact Kloster Irsee, Schwaebisches Tagungs- und Bildungszentrum, Klosterring 4, 87660 Irsee, Germany; telephone +49 8341 906-00; telefax +49 8341 742-78.

Information

New Book: CVD of Nonmetals, edited by William S. Rees, Jr. Written by leading experts in the field, this handbook offers an up-to-date, critical survey of this field of research. Book discusses the basics necessary for any CVD process, precursor requirements with emphasis on materials chemistry, common structures of reactants and substrates, and reaction control for a broad range of compositions including superconducting, conducting, semiconducting, insulating, and structure materials. Technological issues, such as reactor geometries and operation parameters are assessed, and viability of the method, both technically and economically in comparison to other techniques for preparation of thin films is discussed. Relevant materials and technical data are collected in tables throughout. Publ. 1996; price 238 DM; 391 pp.; ISBN 3-527-29295-0. Contact VCH, Pappelallee 3, D- 69469 Weinheim, Bundesrepublik Deutschland, Germany; telephone +49 6201 6060; telefax +49 6201 606328.

New Volumes in Series: Studies of High Temperature Superconductors: Advances in Research and Applications, edited by Anant Narlikar. Volume 21: Conductor Development of High Temperature Superconductors, includes the following topics -- textured BSCCO superconductors obtained via laser-induced directional solidification; the superconducting and microstructural behavior of YBa2Cu3Oy and YBa2Cu3Oy + Y2BaCuO5 superconductors prepared by the melt-textured growth processes; development of Bi-2212/Ag wires for magnet applications; a novel process for quick synthesis of yttrium-based HTSC; Jc property and microstructure of Bi-2223 tapes made using Ag-Cu alloy sheaths doped with Ti, Zr, or Hf; fabrication of Bi-2212/Ag composite tapes and coils; critical currents in silver-sheathed (Bi,Pb)2Sr2Ca2Cu3O10 tapes; high critical current densities in silver-sheathed Bi-2223 tapes; and investigation on critical current and microstructure of high-Tc Y-Ba-Cu- O superconductors. Publ. 1997; 260 pp.; price $93; ISBN 1-56072-419-6.

Volume 22: Critical Current, Flux Pinning, and Optical Studies of High- Temperature Superconductors, includes the following topics-- flux pinning in melt-processed RE123 superconductors, critical current and flux pinning in YBa2Cu3Oy crystals prepared by melt-textured growth method, ac susceptibility and intergranular critical state in high-Tc superconductors, electronic states of high-Tc superconductors probed by radiation-induced disorder, influence of light on copper-oxide superconductors, low-temperature optical spectroscopy of YBaCuO thin films, and charge dynamics in normal and superconducting states.

Contact Nova Science Publishers, Inc., 6080 Jericho Turnpike - Suite 207, Commack, NY 11725; telephone (516) 499-3103; telefax (516) 499- 3146; e-mail novasci1@aol.com.

New Book: The Theory of Superconductivity in the High-Tc Cuprate Superconductors, by P. W. Anderson. Full presentation of the author's theory of high-Tc superconductivity in the cuprates and the many fundamentally new ideas. Book also discusses experimental progress for both normal and superconducting states. Latest advances are contained in a selection of reprints and preprints of recent work by Anderson and collaborators. Publ. 197; 352 pp.; price $49.50; ISBN 0-691-04365-5. Contact Princeton University Press, c/o California/Princeton Fulfillment Services, Inc., 1445 Lower Ferry Road, Ewing, NJ 08618; telephone (800) 777-4726; telefax (800) 999-1958; e-mail orders@cpfs.pupress.princeton.edu.

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. E-mail: MITRA@AMESLAB.GOV or MITRA@IASTATE.EDU.

Project Director/Editor: Sreeparna Mitra Science Editor: John R. Clem High-Tc Update, Vol. 11, #9, May 1, 1997.