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.
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.
Vortex-Lattice Melting
A high-accuracy adiabatic specific-heat experiment on YBa2Cu3O6.94 (Y- 123) has been performed by M. Roulin et al. (Geneve) to observe the calorimetric signature of vortex-lattice melting. The results are in excellent agreement with the H-T (field-temperature) melting line previously determined by resistance and magnetization measurements. The authors' results are consistent with a second-order transition, as the authors find no evidence for a latent heat. The specific heat of the vortex liquid is found to be larger than that of the vortex solid.
Simultaneous measurements of the resistivity and local magnetization using microscopic Hall sensors have been carried out by D. T. Fuchs (Weizmann Institute) et al. on Bi2Sr2CaCu2O8+d (Bi-2212) crystals as a function of applied field and temperature. The resistivity onset is found to occur concurrently with the first-order vortex-lattice phase transition determined by the equilibrium magnetization step.
Intrinsic Josephson Junctions
Pronounced structures in the current-voltage characteristics of intrinsic Josephson junctions in the high-Tc superconductors Tl2Ba2Ca2Cu3O10 (Tl-2223) and Bi2Sr2CaCu2O8+d (Bi-2212) have been observed by K. Schlenga (Erlangen) et al. The structures appear well below the superconducting gap, independent of sample geometry, magnetic field, and temperature up to 0.5 Tc. The authors discuss possible explanations and show that the structures could be explained by a single peak in the quasiparticle current, possibly arising from subgap structure in the quasiparticle density of states.
123
The dielectric tensor in YBa2Cu3O7-d (Y-123) has been measured by J. Kircher et al. (MPI-Stuttgart) using far-infrared ellipsometry with synchrotron radiation. The authors find that the in-plane and out-of- plane components of the dielectric tensor follow power laws close to those predicted by D. G. Clarke et al. [Phys. Rev. Lett. 74, 4499 (1995)] for inter- and intra-Luttinger-liquid transport.
A new method of cleaving YBa2Cu3O7-d single crystals has been developed by S. Ratz (Frankfurt) et al. A device called a micromilling machine allows the removal of very thin surface layers from the sample by a diamond blade. The resulting surfaces yield high-quality LEED (low- energy electron-diffraction) patterns and highly reproducible angle- resolved photoelectron spectra. Features observed by previous authors (the Fermi edge and the sharp 1 eV structure) also appear.
The hysteretic magnetization and the magnetic relaxation of an Yb-123 single crystal have been investigated by M. Werner (Atominstitut-Wien) et al. using SQUID and capacitance torque magnetometers. The results do not show scaling of the magnetic relaxation curves of the type proposed by L. F. Cohen et al. [Physica C 230, 1 (1994)].
As reported by A. Ignatiev et al. (Houston), photo-assisted metalorganic chemical vapor deposition (PhAMOCVD), when applied to the high-rate growth of YBCO films, results in thick films with crystalline quality approaching that of single-crystal samples. Such films show reduced Jc with increasing thickness primarily because the pinning responsible for high Jc in YBCO films is localized near the film-substrate interface, and the thicker films have few pinning centers in their bulk. The authors found that the pinning centers created in a thick YBCO film upon 1 MeV ion irradiation resulted in a significant increase of Jc beyond the 1 x 10^6 A/cm^2 level.
The single-crystal susceptibility and magnetization hysteresis of YBa2Cu3O7 and YBa2Cu3O6.6 with Tc = 90 K and 58 K, respectively, have been measured by A. I. Rykov et al. (SRL-ISTEC) on twin-free samples. The authors found that the critical current density of untwinned overdoped YBa2Cu3O7 is much less than that of both oxygen-deficient and twinned crystals.
Using the solute-rich-liquid crystal-pulling (SRL-CP) method, H. Kutami (SRL-ISTEC) et al. have grown a pure single crystal of YBa2Cu3O7-d. The authors annealed the twinned crystal at 400^oC under uniaxial compression in an oxygen atmosphere to obtain a superconducting twin- free single crystal. SQUID magnetization measurements on the twin-free crystal showed an onset Tc = 88 K.
Using a vibrating-sample magnetometer (VSM) and a hybrid magnet, G. C. Han (Tohoku) et al. have measured the magnetic hysteresis of quench- melt-growth-processed YBa2Cu3O7-d over a wide temperature and field range (4.2 K <= T < 91 K and 0 <= H < 23 T). The magnetization loops show different characteristics in different temperature regions. The curves at different temperatures were found to scale within certain temperature regions.
The influence of thermal cycling on the levitation force of vertical- gradient-freeze (VGF) melt-textured YBa2Cu3O7-d has been investigated by M. Ullrich et al. (Goettingen). The levitation force decreased with increasing numbers of thermal cycles from room temperature down to the boiling point of liquid nitrogen. The decrease could be explained by the generation and propagation of cracks, which decreased the radii of the screening currents. In addition, water condensing at the surface of the superconductor leads to a decomposition of the superconducting YBa2Cu3O7-d phase and produces large nonsuperconducting areas.
Low-angle grain boundaries and their intersections in melt-textured YBa2Cu3O7-d have been studied by M. K. Mironova et al. (TCSUH) using transmission electron microscopy (TEM). Most of the boundaries were found to be strongly coupled, but short pieces that compensate for large strains between grains can contain several sets of closely spaced dislocations. This arrangement can result in weak-link behavior even in the case of low-angle grain boundaries.
A paper by N. Vandewalle et al. (Liege) presents evidence for fractal grain boundaries in melt-textured Y-123, Dy-123, and Er-123. A universal fractal dimension close to 7/3 is found. The authors present a statistical model that predicts this value of the fractal dimension.
Two papers by M. P. Delamare (Caen) et al. report studies of the influence of a combination of CeO2 and PtO2 additions on the microstructure and critical current density of melt-textured YBa2Cu3O7-d samples. The authors find that the Ce and Pt additions greatly enhance the 77 K critical current density to levels of over 4 x 10^4 A/cm^2 in a field of 1 T.
A preprint by M. Chopra (Columbia) et al. reports a systematic analysis of the effects of the addition of Y2BaCuO5 (211) particles on the critical current density and volume pinning force in melt-textured YBa2Cu3O7-d (123). The authors determine the optimum initial volume of 211 that maximizes the critical current density at various magnetic fields.
As reported by N. Vilalta et al. (Barcelona), in melt texturing YBa2Cu3O7-d, the most efficient procedure to reduce the size of Y2BaCuO5 (211) precipitates is to increase the concentration of nucleation centers present in the peritectic decomposition of YBa2Cu3O7-d (123). A small concentration (0.3-1 wt%) of CeO2 has a strong influence on the solidification process and on the size of the 211 precipitates. The authors find evidence for the nucleation of 211 precipitates on Y2O3 nanoparticles when CeO2 is added. The Y2O3 results from the reaction between 211 and CeO2.
Bi Cuprates
A multi-terminal experiment on Bi2Sr2CaCu2O10+d (Bi-2212) single crystals in zero magnetic field has been carried out by Y. M. Wan (National Tsing Hua) et al. to study the nature of the resistive transition. The current-voltage characteristics were found to be linear in the normal state but nonlinear in the superconducting state and through the normal-superconducting transition. The authors explain the nonlinear features in terms of in-plane thermal excitation of vortices and out-of-plane Josephson interactions.
Measurements of the ab-plane resistivity of Y-doped Bi-2212 single crystals are reported by N. L. Wang et al. (Darmstadt). The authors find a trend of resistivity saturation for samples with high Y concentrations and explain this effect in terms of the Ioffe-Regel limit for metallic resistivity.
The flux-creep behavior in high-quality Bi2Sr2CaCu2O8+d (Bi-2212) single crystals has been examined by L. F. Cohen (Imperial) et al., who measured the dynamic relaxation of the magnetization using a vibrating- sample magnetometer. The authors attribute the magnetization irreversibility to bulk pinning at low temperatures and to edge barriers (including surface and geometric barriers) at high temperatures. The authors find that the increase in current density at the anomalous arrowhead feature of the magnetization is related to the penetration of a Bean-type profile through the sample at a field H*. At H* the vortex lattice softens and flux creep is enhanced. The fast-creep regime survives over a narrow field range up to a field H_b(T), which the authors associate with the irreversibility line of the bulk pinning. Apart from the temperatures and fields where the arrowhead is observed, the creep rate has a similar normalized field dependence at all temperatures.
Magnetization studies of as-grown and 200 MeV Ag-ion-irradiated Bi-2212 single crystals are reported by A. K. Pradhan (Indore) et al. The authors found that the irradiation shifted the irreversibility line (IL) to higher temperatures, enhanced the magnetic hysteresis, and caused the double-peak anomaly in the magnetization hysteresis to disappear. The maximum shift of the IL was observed for a fluence level of 2.5 x 10^[11] ions/cm^2, for which B_[phi] = 5 T. A second paper by A. K. Pradhan et al. reports the influence of oxygen- and argon-annealing on the above effects.
A quantitative comparison between the magnetically induced ac losses and transport current losses in silver-sheathed (Bi,Pb)2Sr2Ca2Cu3O10+d (Bi- 2223) tapes has been made by Y. Fukumoto (Brookhaven) et al. The authors find no substantial difference in the ac losses measured by the two techniques when the induced or applied currents are below the critical current I_c. They also stress that a meaningful comparison can be made only when based on the normalized currents (with respect to the respective deduced critical currents) rather than on the amplitudes of the surface magnetic fields.
The coefficients of the thermal expansion parallel (alpha_[a,b]) and perpendicular (alpha_c) to the CuO2 planes and the specific heat c_p of a Bi-2212 single crystal have been measured by H. Kierspel (Koeln) et al. The authors find a clear anomaly in alpha_[a,b] at Tc but none in alpha_c. By comparing the anomalies in c_p and alpha_[a,b], the authors determine the uniaxial pressure dependence of Tc in Bi-2212 for pressure parallel to the CuO2 planes: dTc/dP_[a,b] = 0.9(1) K/GPa. The authors also observed a jump-like increase of the thermal expansion parallel to the c axis at 120 K, suggesting a structural instability at this temperature.
A preprint by Y.-L. Wang (Brookhaven) et al. proposes a two-step process for the formation of c-axis-aligned (Bi,Pb)2Sr2Ca2Cu3O10+d (Bi-2223) platelets in a silver sheath. The process involves (a) the formation of c-axis-aligned (Bi,Pb)2Sr2CaCu2O8+d (Bi-2212) at an early stage of heat treatment and (b) the subsequent intercalation of Ca-CuO2 layers to form Bi-2223.
The decomposition pathway of Bi-2212 with 0, 2, and 10 wt% Ag has been examined by L. Margulies et al. (Ames Lab, Iowa State) at oxygen partial pressures P(O2) of 0.01, 0.21, and 1 bar using scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS) and microprobe analysis of oil-quenched samples. The authors constructed a series of pseudo-ternary phase diagrams at each P(O2) to describe the evolution of the phase assemblage with temperature. A related preprint by L. Margulies et al. reports measurements of the depression of the decomposition temperature of Bi-2212 as a function of the carbon content.
Other Cuprates
By using a high-pressure, high-temperature technique, P. Bordet et al. (Grenoble) have succeeded in substituting Au for Hg in mercury cuprate superconductors. The authors find that Au substitution leads to overdoping of the CuO2 layers. This effect can be used to raise the Tc of HgBa2Ca4Cu5O12+d (Hg-1245). While unsubstituted samples of Hg-1245 normally obtained by the high-pressure, high-temperature technique are in an underdoped state with a Tc around 100 K, gold substitution raises Tc to 110 K.
The structure of the superconducting (Tc = 25 K) layered copper oxychromate Tl3(CrO4)Sr8Cu4O16 has been determined by C. Michel et al. (Caen) using powder neutron diffraction. The main features of the structure are waviness of the CuO2 layers and perfect flatness of the (TlCr)O layers.
Using selected-area electron diffraction (SAED) and high-resolution transmission electron microscopy (HRTEM), J. Ramirez-Castellanos (NIRIM and Tsukuba) et al. have studied the structure of a new ordered cuprate with a composition close to Sr3Ca3Cu6O15+-d, which was found in a superconductive specimen prepared by a high-pressure technique. This phase has a wavy modulated superstructure.
Pb2Sr2Ce0.5Ca0.5Cu3O8 and Pb2Sr2Ln1-xCaxCu3O8 with Ln = Pr, Tb and x = 0.0, 0.5 have been studied by K. R. Pedersen and J.-E. Jorgensen (Aarhus) using rare earth L_[II,III]-edge XANES spectroscopy. The partial oxidation of Ce in Pb2Sr2Ce0.5Ca0.5Cu3O8 prevents the formation of electron holes in the CuO2 layers and thereby explains the lack of superconductivity in this compound.
Borocarbides
Electronic and magnetic properties of single-crystal YNi2B2C from [11]^B and [89]^Y NMR and magnetic susceptibility measurements are reported by B. J. Suh et al. (Ames Lab). The authors note that the observed enhancement of the [11]^B nuclear-spin-lattice relaxation (NSLR) in the normal state of YNi2B2C is not due to effects of antiferromagnetic fluctuations of Ni magnetic moments but due to an increase in the s-band spin susceptibility with decreasing temperature as reflected in the temperature dependence of the Knight shift. In this respect, the authors conclude that YNi2B2C is different from the cuprate high-Tc superconductors. The negative hyperfine interaction at the [89]^Y site is consistent with a transferred hyperfine interaction involving polarization of s-like electrons at the Y site by d electrons. In the superconducting state, the 11B NSLR is found to fit a BCS temperature dependence with a superconducting gap parameter, as expected from properties of Fermi liquids in the normal state.
Synthesis of YNi2B2C and LuNi2B2C by a powder metallurgy method is reported by H. Szillat et al. (MPI-Stuttgart). The samples, prepared by mixing powders in stoichiometric proportions, isostatically pressing at 630 MPa, and annealing at 1300^oC for 96 hours, yielded compounds with a Tc of 24 K. Results of this study also show that an optimization of Tc is possible by varying the boron content, and a reduced mole fraction of boron from the ideal stoichiometric proportions decreases the Tc value.
Thin Films
Epitaxial thin films of Tl2Ba2CuO6 (Tl-2201) on SrTiO3 have been prepared by Z. F. Ren (SUNY-Buffalo) et al. using sputtering and post- deposition annealing. The films were deposited onto (100) SrTiO3 single-crystal substrates by rf magnetron sputtering and then annealed using a two-step process. The annealed films typically exhibited transition temperatures of about 11 K. Subsequent re-annealing to optimize the oxygen doping in the film, however, resulted in an increase in the transition temperature, and optimally re-annealed films exhibited transition temperatures of about 83 K. Studies by x-ray diffraction and transmission electron microscopy revealed that both the 11 K and 83 K films have a tetragonal crystal structure.
The effects of fast-neutron and Au-ion irradiation on Tl-2212 and Tl- 2223 thin films have been investigated by G. S. Hosseinali (Atominstitut-Wien) et al. Large enhancements of flux pinning and Jc were observed, particularly at high temperatures, without significant changes of Tc. STM studies of the surface morphology before and after ion irradiation showed that holes with diameters in the range 20-50 nm were produced after Au irradiation to a fluence of 1.5 x 10^[15] m^[-2].
A new method for the precise measurement of the critical current density Jc in superconducting thin films is reported by M. Baziljevich (Oslo) et al. It is based on magneto-optical (MO) imaging of the flux distribution normal to the film plane. Using recent theory for the transverse geometry, the authors show that Jc can be determined simply by locating the position of the annihilation zone formed by remagnetization of the thin sample in the remanent state. This new approach is shown to be insensitive to the distance of the MO indicator- sample distance. The authors demonstrate the method using a 0.8 mm wide strip of a laser-ablated YBa2Cu3O7-d film in the temperature range 25-80 K.
Mode coupling in a superconducting parallel-plate resonator with an outer conductive enclosure has been studied by F. Gao et al. (Illinois- Urbana). The model developed by the authors can be used to extract the intrinsic Q of the superconducting resonator.
A preprint by N. Dieckmann et al. (Hamburg) reports the use of scanning micro-Raman spectroscopy (SMRS) to characterize the epitaxial film quality and the use of low-temperature scanning laser microscopy (LTSLM) to image electrical properties of YBa2Cu3O7-d devices locally in both lateral dimensions. The authors have investigated the properties of crossovers used in flux transformers, patterned in a multilayer process on SrTiO3 (100) substrates. The authors find a correlation between an inhomogeneous superconducting performance and a disturbance of epitaxy on locations where the crossovers pass edges of the underlying bridge. The distribution of oxygen is not affected at these points.
Applications
As discussed by W. M. Huber (Regensburg) et al., epitaxial YBa2Cu3O7-d thin films, grown with a controllable misalignment between the c axis and the surface normal, exhibit a sensitive photoresponse to far- infrared laser radiation at temperatures below Tc. While no photoresponse was observed in c-axis normal films, a sensitivity of 0.2 V/W was measured at a wavelength of 432 micrometers for a film with a 20 degrees c-axis tilt. Difference mixing of two laser modes also has been demonstrated at intermediate frequencies between 200 kHz and 6 MHz. Both mixing and video detection are believed to originate in the ac Josephson effect: The effect of the tilted growth is to allow a component of the radiation field to be applied along the c axis, thus modulating the relatively weak Josephson coupling in this direction.
A preprint by P. C. Shan (Southern Methodist) et al. reports studies of the semiconducting phases of oxygen-deficient YBa2Cu3O6+x thin films for possible application as a bolometer for uncooled infrared detection. The authors estimate that amorphous semiconducting YBCO bolometers could have a responsivity as high as 1.7 x 10^5 V/W and a detectivity as high as 7.2 x 10^8 cm Hz^[1/2]/W for a 1 micro-amps bias current and frame frequency of 30 Hz, if integrated with a typical air-gap thermal isolation structure.
Theory
As emphasized by K. Ziegler (MPI-Stuttgart) et al., it has been known for some time that, in three dimensions, arbitrarily weak disorder in unconventional superconductors with line nodes gives rise to a nonzero residual density of zero-energy quasiparticle states N(0), leading to characteristic low-temperature thermodynamic properties similar to those observed in cuprate and heavy-fermion systems. However, in a strictly two-dimensional model possibly appropriate for the cuprates, it has been argued that N(0) vanishes. The authors have performed exact calculations for d- and extended s-wave superconductors with Lorentzian disorder and similar models with continuous disorder distribution, and they find that in these cases the residual density of states is nonzero even in two dimensions.
Strong evidence has been found by M. Franz et al. (McMaster) for the localization of low-energy quasiparticle states in disordered d-wave superconductors. Within the framework of the Bogoliubov-de Gennes (BdG) theory applied to the extended Hubbard model with a finite concentration of nonmagnetic impurities, the authors carried out a fully self- consistent numerical diagonalization of the BdG equations on clusters containing up to 50 x 50 sites. Localized states were identified by probing their sensitivity to the boundary conditions and by analyzing the finite-size dependence of inverse participation ratios.
According to K. Levin et al. (Chicago), d-wave symmetry of the order parameter is a general consequence of superconductivity driven by repulsive interactions. Van Hove (or flat-band) effects, deriving from the two dimensionality of the CuO2 planes, are important in stabilizing this state. By extending the original Kohn-Luttinger picture to a 2D lattice, the authors find that the screened Coulomb term has important wave-vector structure which leads to d_[x^2-y^2] superconductivity.
The behavior of the quasiparticle density of states (QDOS) in strong- coupling superconductors has been studied by Y. Yokoya and Y. O. Nakamura (Science University of Tokyo) within the framework of the Eliashberg theory with an energy-dependent Lorentzian electronic density of states (EDOS). The calculations show that when the EDOS has structure, it can give additional structure to the QDOS beyond the structure produced by the electron-phonon interaction. The authors also find large values of the energy gap ratio, 2Delta_0/k_BTc, and an unusual band-filling dependence of this ratio. When the electron-phonon coupling becomes strong, the gap ratio can have its maximum value far from half-filling.
A preprint by V. M. Vinokur (Argonne) et al. discusses the low- temperature dynamics of an elastic manifold driven through a random medium. For driving forces F well below the T = 0 depinning force, the elastic manifold advances via thermally activated hops over the energy barriers separating favorable metastable states. The authors show that the distribution of waiting times for these hopping processes scales as a power law and that the average velocity behaves as v proportional to exp(-AF^[-mu]), where A is a constant and mu is a characteristic exponent.
Molecular dynamics simulations of a two-dimensional vortex array driven by a uniform current through random pinning centers at zero temperature have been performed by M. C. Faleski et al. (Syracuse). The authors find two types of flow near the depinning threshold. For weak disorder, the vortex array contains few dislocations and moves via correlated displacements of patches of vortices. Following the suggestion of J. Hu and R. M. Westervelt [Phys. Rev. B 51, 17279 (1995)], who saw similar behavior in magnetic bubble arrays, the authors refer to this as crinkle motion. As the strength of disorder increases, a crossover to a spatially inhomogeneous regime of plastic flow occurs, with a very defective vortex array and a channel-like structure of the flowing regions.
The nonlocal conductivity in the vortex-liquid regime of a two- dimensional superconducting film has been studied theoretically by R. Wortis (Illinois and Bell Labs) and D. A. Huse (Bell Labs) using the time-dependent Ginzburg-Landau equations. The authors find a portion of the vortex-liquid regime in which the nonlocal ohmic conductivity in real space is negative over a distance several times the spacing between vortices.
A superconductor in contact with a normal metal not only induces superconducting correlations (the proximity effect) but also modifies the local density of states N(E,x) at some distance x from the interface. A preprint by W. Belzig (Karlsruhe) et al. reports calculations of N(E,x) for a superconductor-normal heterostructure. The results are in good agreement with recent experiments.
Other Activities
The formation of superconducting oxides in the series YbnBa2nCu3n+1Ox (n = 1, 2, infinity; Yb-124, Yb-247, etc.) has been studied by R. Kontra (MIT) et al. using high-resolution and conventional transmission electron microscopy, energy-dispersive x-ray spectroscopy, and powder x- ray diffraction. The authors find evidence for intercalative formation of Yb-247 and Yb-124 via the decomposition of Ba2Cu3O5 to BaCuO2.
Overviews
A brief review of current theories of the vortex-lattice melting transition in the high-temperature superconductors has been prepared by D.J.C. Jackson and M. P. Das (Australian National). Section headings include Anderson-Kim flux creep, giant flux creep, collective pinning, thermal fluctuations and flux cutting, vortex entanglement, vortex-glass phase, what the experiments say, theoretical examination of the melting transition, and the vortex gas (58 refs.).
A paper by C. W. Chu (TCSUH) summarizes efforts to raise Tc over the last ten years in HTS materials and addresses future prospects for Tcs above the current records of Tc = 134 K (ambient conditions) and Tc = 164 K (under high pressure). A summary of characteristics, properties, and significant results in all families of high-Tc superconductors are presented (48 refs.).
Ph.D. Thesis
The thesis of S. H.-R. Clerc (Swiss Federal Institute, Zurich) reports results of ac loss measurements in Bi-2223/Ag tapes which show that in multifilamentary conductors, the losses and granularity effects are smaller than those in monocore tapes. Measurements of losses due to interfilamentary coupling currents are presented, and the authors find that a reduction in these frequency-dependent losses can be achieved by twisting the filaments. Coupling-loss calculations using a rectangular cross section show that the losses depend on the height-to-width aspect ratio. (49 refs.)
Contributed by John R. Clem and Sreeparna Mitra
This section describes progress in manufacturing, product development, and technology transfer in the high-Tc superconductivity field. Please send your contributions (product development information, news regarding technology transfer efforts, or any information you would like to share about your corporation or laboratory) to the editor.
A joint agreement was announced between Conductus, Inc., and Bell Labs to produce a cryocooled filter/amplifier subsystem for Personal Communications Service (PCS) base stations. Conductus also announced the delivery of a prototype of the receiver portion of the subsystem which included a tower-top electronics package. The unit provides multiple-receiver circuits to improve sensitivity offered for low-power PCS handsets. Ultimately, the subsystem is expected to include a lower loss and more selective transmission filters along with the receivers and related circuits for use with the base stations. Conductus and Bell Labs expect to demonstrate the prototype subsystem by fall 1996. The current agreement follows the successful demonstration of a superconducting interference-reduction filter last summer. For further information, contact Duncan MacMillan, Vice President for Technology Programs, Conductus, Inc., 969 West Maude Ave., Sunnyvale, CA 94086; telephone (408) 523-9950; telefax (408) 523-9999.
Aiming to develop conductors suitable for ac applications, researchers at Alcatel Alsthom Recherche have successfully fabricated twisted powder-in-tube (PIT) conductors with resistive matrix materials suitable for ac applications at 50 Hz. Several different Bi-2212 conductors with a twist pitch of 7-9 mm, an Ag-Pd matrix, and a cross section of 2.9 x 0.54 mm^2 have been realized. Transport currents of 400-500 A have been measured in these conductors at 4.2 K in self-fields, which indicates that the critical current density in the wire had reached a threshold value of 30,000 A/cm^2. The conductor contains a superconducting volume fraction of 35%, which results in a critical current density in the superconductor of 90,000 A/cm^2. At liquid nitrogen temperatures, a critical current of 18 A was carried in this conductor, and further development of Bi-2223 conductors suitable for this temperature range is under progress. Development will also now be directed towards fabrication of longer length conductors and test coils. For further information, contact Dr. P. F. Herrmann, Alcatel Alsthom Recherche, Route de Nozay, 91460 Marcoussis, France; telephone +33 1 64 49 1000; telefax +33 1 64 49 0694.
Contributed by Sreeparna Mitra
Roman Adam, Witold Kula, J. M. Murduck, C. Pettiette-Hall, and Roman Sobolewski, "Laser-Induced Modification of the Critical Current in Y-Ba- Cu-O Step-Edge Josephson Junctions." To be published in the Proc. of the XXI Int. Conf. on Low Temperature Phys. (LT21), Prague, Czech Republic, Aug. 8-14, 1996 and Czechoslovak J. Phys. Department of Electrical Engineering and Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14627; e-mail adam@ee.rochester.edu.
S. A. Agnihotry, Rashmi, S. Chandra, P. P. Bakare, and S. K. Date, "Superconductivity in Sb Incorporated Bi-Sr-Ca-Cu-O (BSSCCO) System." To be published in Physica C, Vol. 261 (in press). National Physical Laboratory, New Delhi 110012, INDIA; telefax +91 11 575 2678.
V.P.S. Awana, S. K. Malik, and W. B. Yelon, "Structural Aspects and Superconductivity in Oxygen-Deficient Y1-xCaxBa2Cu3O7-y (y ~~ 0.3) System: A Neutron-Diffraction Study." To be published in Physica C, Vol. 261 (in press). Departamento de Fisica, Universidade Federal de Pernambuco, 50670-901, Recife-PE, BRAZIL; e-mail awana@npd.ufpe.br.
V.P.S. Awana, Latika Menon, and S. K. Malik, "Synthesis, Superconductivity and Magnetism of RSr2Cu2NbO7+d Compounds (R = Y, Pr, and Gd)." To be published in Physica C, Vol. 261 (in press). Contact S. K. Malik, Tata Institute of Fundamental Research, Bombay 400 005, INDIA; e-mail skm@tifrvax.bitnet.
M. Baziljevich, T. H. Johansen, H. Bratsberg, Y. Galperin, P. E. Lindelof, Y. Shen, and P. Vase, "New Simple Method to Measure Jc in Superconducting Films Using Magneto-Optics." Department of Physics, University of Oslo, P.O. Box 1048, Blindern, 0316 Oslo, NORWAY.
W. Belzig, C. Bruder, and Gerd Schoen, "Local Density of States in a Dirty Normal Metal Connected to a Superconductor." Submitted to Phys. Rev. B. Institut fuer Theoretische Festkoerperphysik, Universitaet Karlsruhe, D-76128 Karlsruhe, GERMANY.
I. Yu. Bezotosny, V. F. Elesin, V. P. Mar'in, A. A. Sinchenko, V. F. Vikulov, I. S. Lyubutin, and K. V. Frolov, "Influence of Defects Produced by Fast Electrons on Superconducting and Magnetic Properties of YBa2(Cu1-xFex)3O7-y System." To be published in Physica C (in press). Moscow Engineering-Physical Institute, 115409 Moscow, RUSSIA; e-mail root@magnet.crystal.msk.su.
A. Bock, R. Kuersten, M. Bruehl, N. Dieckmann, and U. Merkt, "Desorption of Oxygen from YBa2Cu3O6+x Films Studied with Raman Spectroscopy." To be published in Phys. Rev. B. Institut fuer Angewandte Physik und Zentrum fuer Mikrostrukturforschung, Universitaet Hamburg, Jungiusstrasse 11, D-20355 Hamburg, GERMANY; telephone +49 40 4123 2688; telefax +49 40 4123 4368; e-mail bock@physnet.uni-hamburg.de. 44.30.+v; 68.45.Da; 74.72.Bk; 74.76.Bz; 78.30.Er.
P. Bordet, S. Le Floch, J. J. Capponi, C. Chaillout, M. F. Gorius, M. Marezio, J. L. Tholence, and P. G. Radaelli, "Gold Substitution in Mercury Cuprate Superconductors." To be published in Physica C (in press). Laboratoire de Cristallographie CNRS-U.J.F., BP 166, F-38042 Grenoble Cedex 9, FRANCE; telefax +33 76 88 10 38; e-mail bordet@labs.polycnrs-gre.fr.
G. Brandstaetter, G. Samadi Hosseinali, K. Kundzins, Y. Meslmani, F. M. Sauerzopf, W. Straif, B. Starchl, and H. W. Weber, "Irreversible Properties of Tl-Based High-Tc Superconductors." Submitted to the Proc. of the 16th Int. Cryogenic Eng. Conf. and the Int. Cryogenic Mater. Conf. (ICEC 16/ICMC), Kitakyushu, Japan, May 20-24, 1996. Atominstitut der OEsterreichischen Universitaeten, Schuettelstrasse 115, A-1020 Wien, AUSTRIA; e-mail brandstae@ati.ac.at.
G. Brandstaetter, F. M. Sauerzopf, and H. W. Weber, "Fast Neutron Irradiation Effects on Jc in Tl-Based High Temperature Superconductors." Submitted to the Proc. of the Eighth Int. Workshop on Critical Currents in Supercond. (8th IWCC) Kitakyushu, Japan, May 27-29, 1996. Atominstitut der OEsterreichischen Universitaeten, Schuettelstrasse 115, A-1020 Wien, AUSTRIA; e-mail brandstae@ati.ac.at.
G. Brandstaetter, F. M. Sauerzopf, H. W. Weber, and B. D. Veal, "Flux Pinning in Two-Dimensional High Temperature Superconductors." Submitted to the Proc. of the XXI Int. Conf. on Low Temperature Physics (LT 21), Prague, Czech Republic, Aug. 8-14, 1996. Atominstitut der OEsterreichischen Universitaeten, Schuettelstrasse 115, A-1020 Wien, AUSTRIA; e-mail brandstae@ati.ac.at.
F. Chen, X. D. Qiu, Y. Cao, L. Gao, Y. Y. Xue, C. W. Chu, and Q. Xiong, "High Pressure Study of Hg-Based Cuprates." Preprint #96:058; submitted to the Proc. of the 10th Anniv. HTS Workshop on Physics, Materials, and Applications, Houston, TX, March 12-16, 1996 (World Sci., Singapore). 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.
Manoj Chopra, Siu-Wai Chan, R. L. Meng, and C. W. Chu, "Y2BaCuO5 Addition and Its Effects on Critical Currents in Large Grains of YBa2Cu3O7-d: A Quantative Microstructural Study." To be published in J. Mater. Res. Henry Krumb School of Mines, Columbia University, New York, NY 10027. Key words: superconductors, electrical properties, polycrystal, melt textured, percolation, critical current, flux pinning, quantitative optical microscopy.
C. W. Chu, "Superconductivity Above 90 K and Beyond." Preprint #96:059; submitted to the Proc. of the 10th Anniv. HTS Workshop on Physics, Materials, and Applications, Houston, TX, March 12-16, 1996 (World Sci., Singapore). 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.
J. A. Clayhold, Y. Y. Xue, C. W. Chu, J. N. Eckstein, and I. Bozovic, "Puzzling Behavior of the Electrothermal Conductivity of High-Tc Superconductors." Preprint #96:050; submitted to the Proc. of the 10th Anniv. HTS Workshop on Physics, Materials, and Applications, Houston, TX, March 12-16, 1996 (World Sci., Singapore). 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.
Stephan H.-R. Clerc, "ac Losses of Mono- and Multifilamentary High-Tc Superconducting (Bi,Pb)2Sr2Ca2Cu3O10/Ag Tapes." Paul Scherrer Institut, CH-5232 Villigen PSI, SWITZERLAND; telephone +41 56 99 21 11; telefax +41 56 98 23 27; e-mail clerc@psi.ch.
L. F. Cohen, J. T. Totty, G. K. Perkins, R. A. Doyle, and K. Kadowaki, "Flux Creep Associated with Bulk Pinning and Edge Barriers in BSCCO 2212 Single Crystals." Submitted to Physica C. Blackett Laboratory, Imperial College, Prince Consort Road, London SW7 2BZ, UNITED KINGDOM; telephone +44 171 594 7598; telefax + 44 171 594 7580; e-mail 1.cohen@ic.ac.uk. Key words: flux creep, flux pinning, magnetization.
M. P. Delamare, M. Hervieu, J. Wang, J. Provost, I. Monot, K. Verbist, and G. Van Tendeloo, "Combination of CeO2 and PtO2 Doping for Strong Enhancement of Jc Under Magnetic Field in Melt-Textured Superconductor 'YBaCuO.'" To be published in Physica C (in press). Laboratoire CRISMAT, URA CNRS 1318, ISMRA 6, Bd. Marechal Juin, F-14050 Caen Cedex, FRANCE; telephone +33 31 95 26 30; telefax +33 31 95 16 00; e-mail ceram@crismat.ismra.fr. Key words: superconductor, CeO2, PtO2, dopants, critical current density, TEM.
M. P. Delamare, I. Monot, J. Wang, J. Provost, and G. Desgardin, "Influence of CeO2, BaCeO3 or PtO2 Additions on the Microstructure and the Critical Current Density of the Melt Processed YBCO Samples." To be published in Supercond. Sci. & Technol. Laboratoire CRISMAT, URA CNRS 1318, ISMRA 6, Bd Marechal Juin, F-14050 Caen Cedex, FRANCE; telephone +33 31 95 26 30; telefax +33 31 95 16 00; e-mail ceram@crismat.ismra.fr. 74.30.Ci; 61.16.Di; 81.30.Fb.
N. Dieckmann, A. Bock, and U. Merkt, "Spatially Resolved Analyses of Epitaxial and Electrical Properties of YBa2Cu3O7 Devices." To be published in Appl. Phys. Lett. Institut fuer Angewandte Physik und Zentrum fuer Mikrostrukturforschung, Universitaet Hamburg, Jungiusstrasse 11, D-20355 Hamburg, GERMANY; telephone +49 40 4123 42 02; telefax +49 40 4123 63 68; e-mail dieckmann@pysnet.uni.hamburg.de. 78.30.-j; 74.76.Bz; 85.25.Dq.
J. Eisenmenger, C. Brand, and P. Leiderer, "Microbridge on YBa2Cu3O7-d Thin Film Patterned by Reversible Laser Annealing." To be published in Physica C (in press). Contact P. Leiderer, Fakultaet fuer Physik, Universitaet Konstanz, Postfach 5560 M 675, D-78464 Konstanz, GERMANY; telefax +49 7531 3091; e-mail paul.leiderer@uni-konstanz.de. Key words: applications of high-Tc superconductors, metal-insulator transition, oxygen stoichiometry, thin films, laser treatment.
M. C. Faleski, M. C. Marchetti, and A. A. Middleton, "Vortex Dynamics and Defects in Simulated Flux Flow." Submitted to Phys. Rev. B. Department of Physics, Syracuse University, 201 Physics Building, Syracuse, NY 13244; e-mail faleski@npac.syr.edu. 74.60.Ge; 74.60.-w; 62.20.Fe.
M. B. Field, A. Polyanskii, A. Pashitski, D. C. Larbalestier, A. S. Parikh, and K. Salama, "Magneto-Optic Imaging of Melt-Textured YBa2Cu3O6+x Bicrystals." Preprint #96:061; submitted to the Proc. of the 10th Anniv. HTS Workshop on Physics, Materials, and Applications, Houston, TX, March 12-16, 1996 (World Sci., Singapore). 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.
F. C. Fonseca and R. Muccillo, "Properties of Ag-YBa2Cu3O7-d Superconductors Prepared by the Citrate Method." Submitted to Physica C. Instituto de Pesquisas Energeticas e Nucleares, Comissao Nacional de Energia Nuclear, C. P. 11049-Pinheiros, 05422-970 S. Paulo, BRAZIL. Key words: synthesis of Y123-Ag, optical ceramography, flexural strength, electrical resistivity.
M. Franz, C. Kallin, and A. J. Berlinsky, "Impurity Scattering and Localization in d-Wave Superconductors." Department of Physics and Astronomy and Brockhouse Institute for Materials Research, McMaster Universiity, Hamilton, Ontario L8S 4M1, CANADA.
D. T. Fuchs, E. Zeldov, D. Majer, R. A. Doyle, T. Tamegai, S. Ooi, and M. Konczykowski, "Simultaneous Resistivity Onset and First-Order Vortex- Lattice Phase Transition in Bi2Sr2CaCu2O8." To be published in Phys. Rev. B. Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 76100, ISRAEL; fndandan@wis.weizmann.ac.il. 74.25.Fy; 74.60.Ec; 74.60.Ge; 74.60.Jg; 74.72.Hs.
Y. Fukumoto, H. J. Wiesmann, M. Suenaga, and P. Haldar, "ac Losses in Silver-Sheathed (Bi,Pb)2Sr2Ca2Cu3O10 Tapes III: Comparison of Magnetically Induced and Transport Current Losses." Submitted to Appl. Phys. Lett. Department of Applied Science, Brookhaven National Laboratory, Upton, NY 11973.
F. Gao, M. V. Klein, J. Kruse, and M. Feng, "Mode Coupling in Superconducting Parallel Plate Resonator with Outer Conductive Enclosure." To be published in IEEE Trans. Microwave Theory Tech. (June 1996). M/A-COM Inc., Microelectronics Division, 100 Chelmsford Street, Lowell, MA 01851; telephone (508) 656-2847; telefax (508) 656-2780; e- mail gao@condor.macom.com.
J. S. Gardner, G. Balakrishnan, D. McK. Paul, and C. Haworth, "Neutron Diffraction and Magnetization Studies of Sr2RuO4 Below 2 K." To be published in Physica C. Department of Physics, University of Warwick, Coventry CV4 7AL, UNITED KINGDOM; telephone +44 1203 523523 ext 2034; telefax +44 1203 692016; e-mail phrqw@csv.warwick.ac.uk. Key words: Sr2RuO4, perovskite structure, neutron powder diffraction, superconductors.
G. C. Han, S. Awaji, K. Watanabe, N. Kobayashi, K. Kimura, and M. Hashimoto, "Magnetization Hysteresis of Quench-Melt-Growth Processed YBa2Cu3O7 in High Fields Up to 23 T." To be published in Physica C (in press). Institute for Materials Research, Tohoku University, Sendai 980-77, JAPAN.
Kikuo Harigaya, "Charge Transfer Excitons in Optical Absorption Spectra of C60-Dimers and Polymers." Physical Science Division, Electrotechnical Laboratory, Umezono 1-1-4, Tsukuba, Ibaraki 305, JAPAN; e-mail harigaya@etl.go.jp or http://www.etl.go.jp/people/harigaya/.
G. Samadi Hosseinali, Y. Meslmani, H. W. Weber, E. Stangl, S. Proyer, and D. Baeuerle, "Surface Morphology of Oxygen-Deficient YBa2Cu3O7-d Thin Films." Submitted to Proc. of ICMC, Kitakyushu, Japan, May 20-24, 1996. Atominstitut der OEsterreichischen Universitaeten, A-1020 Wien, AUSTRIA.
G. Samadi Hosseinali, W. Straif, B. Starchl, K. Kundzins, H. W. Weber, S. L. Yan, M. Manzel, E. Stangle, S. Proyer, D. Baeuerle, R. Cherubini, and T. H. Johansen, "Irradiation Effects on the Critical Currents in TI- 2212 and TI-2223 Thin Films. Submitted to Eighth International Workshop on Critical Currents in Superconductors, (8th IWCC) Kitakyushu, Japan, May 27-29, 1996. Atominstitut der OEsterreichischen Universitaeten, A- 1020 Wien, AUSTRIA.
W. M. Huber, M. Berr, A. Kalbeck, W. Prettl, and P. G. Huggard, "Far Infrared Video Detection and Difference Frequency Mixing with Tilted c- Axis Epitaxial YBa2Cu3O7-d Thin Films." To be published in Appl. Phys. Lett. (in press). Institut fuer Experimentelle und Angewandte Physik, Universitaet Regensburg, D-93040 Regensburg, GERMANY; telephone +49 941 943 2050; telefax +49 941 942 4223; e-mail wolfgang.huber@physik.uni- regensburg.de.
A. Ignatiev, Q. Zhong, P. C. Chou, X. Zhang, J. R. Liu, and W. K. Chu, "Thick Film YBCO Growth by Photo-Assisted MOCVD: Jc Enhancement by Ion Irradiation." Preprint #96:060; submitted to the Proc. of the 10th Anniv. HTS Workshop on Physics, Materials, and Applications, Houston, TX, March 12-16, 1996 (World Sci., Singapore). 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.
Y. Imagawa and Y. Shiohara, "Orientation Control of Pt Added YBa2Cu3O6+x by the Directional Solidification Method." 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: directional solidification, YBCO, orientation control, high Jc.
D.J.C. Jackson and M. P. Das, "Melting of the Flux Line Lattice: A Review." Theory Group, School of Physics, University of Birmingham, Birmingham B15 2TT, ENGLAND. 74.60.Ge; 74.70.
Zdenek Janu, Rudof Tichy, and Xiao-lin Wang, "Flux Dynamics in Bi2Sr2CaCu2O8 Single Crystal." To be presented at the XXI Int. Conf. on Low Temperature Physics (LT 21), Prague, Czech Republic, Aug. 8-14, 1996. Institute of Physics, Czech Academy of Sciences, 250 68 Rez, CZECH REPUBLIC; telefax +42 2 82 12 27; e-mail janu@fzu.cz.
Zdenek Janu, Rudof Tichy, Miloslav Novak, Vladimir Gregor, and Xiao-lin Wang, "Flux Noise in YBaCuO Thin Film and BiSrCaCuO Single Crystal." To be presented at the XXI Int. Conf. on Low Temperature Physics (LT 21), Prague, Czech Republic, Aug. 8-14, 1996. Institute of Physics, Czech Academy of Sciences, 250 68 Rez, CZECH REPUBLIC; telefax +42 2 82 12 27; e-mail janu@fzu.cz.
Zdenek Janu, Rudof Tichy, Frantisek Soukup, Miloslav Novak, and Milan Behensky, "SQUID Magnetometer for HTSC Studies with 100 Phi_0 Hz^[-1/2] Sensitivity Continually Operating in +-28 mT ac Field." To be presented at the XXI Int. Conf. on Low Temperature Physics (LT 21), Prague, Czech Republic, Aug. 8-14, 1996. Institute of Physics, Czech Academy of Sciences, 250 68 Rez, CZECH REPUBLIC; telefax +42 2 82 12 27; e-mail janu@fzu.cz.
Ali E. Khalil, "Fluxon Thermal Motion and Non-Linear Diffusion in High Temperature Superconductors." To be published in Philos. Mag. B. Department of Physics, University of Bahrain, P.O. Box 32038, BAHRAIN.
Ali E. Khalil, "Modes of Disorder and Plastic Flow of Flux Lines in Superconductors." To be published in Phys. Rev. B. Department of Physics, University of Bahrain, P.O. Box 32038, BAHRAIN.
M.K.R. Khan, Yoshihiro Mori, Isao Tanaka, and Hironao Kojima, "Growth and Superconductivity of La2-xCaxCuO4 Single Crystals." To be published in Physica C (in press). Contact Hironao Kojima, Institute of Inorganic Synthesis, Faculty of Engineering, Yamanashi University, Miyamae 7, Kofu, Yamanashi 400, JAPAN; telefax +81 552 54 3035. Key words: single-crystal growth, anisotropic superconductor, electrical resistivity, magnetization.
H. Kierspel, H. Winkelmann, T. Auweiler, W. Schlabitz, B. Buechner, V.H.M. Duijn, N. T. Hien, A. A. Menovsky, and J.J.M. Franse, "Thermal Expansion, Specific Heat, and Uniaxial Pressure Dependences of Tc in Bi2Sr2CaCu2O8+d." To be published in Physica C (in press). II. Physikalisches Institut, Universitaet zu Koeln, Zuelpicher Str. 77, D- 50937 Koeln, GERMANY; telefax +49 221 470 5178; e-mail kierspel@idefix.ph2.uni-koeln.de.
A. M. Kini, K. D. Carlson, H. H. Wang, J. A. Schlueter, J. D. Dudek, S. A. Sirchio, U. Geiser, K. R. Lykke, and Jack M. Williams, "Determination of a Mass Isotope Effect on Tc in an Electron-Donor-Based Organic Superconductor, kappa-(ET)2Cu(NCS)2, Where ET Represents Bis(ethylenedithio)tetrathiasfulvalene." To be published in Physica C (in press). Chemistry and Materials Science Divisions, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, IL 60439; telefax (708) 252 4470; arvind_kini@qmgate.anl.gov.
J. Kircher, R. Henn, and M. Cardona, "Interplane Optical Conductivity of YBa2Cu3O7. I: The Normal State - A Luttinger Liquid?" Max-Planck- Institut fuer Festkoerperforschung, Heisenbergstr. 1, D-70569 Stuttgart, GERMANY. 74.72.-h; 76.30.Pk; 78.20.-e; 78.30.-j.
R. Kontra, A. Otto, and J. B. Vander Sande, "Reaction Paths and Mechanisms for the Formation of Superconducting Oxides in the Rare Earth Ba-Cu-O System. To be published in Physica C (in press). Contact J. B. Vander Sande, Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139.
H. Kutami, Y. Yamada, H. Mori, W. J. Jang, M. Nakamura, Z. Nakagawa, and Y. Shiohara, "Structure Refinement of a Twin-Free Orthorhombic YBa2Cu3Ox Single Crystal Prepared by SRL-CP Method." To be published in Physica C (in press). Research Laboratory of Engineering Materials, Tokyo Institute of Technology, Nagatsuta 4259, Midori-ku, Yokohama-shi, Kanagawa 226, JAPAN.
K. Levin, D. Z. Liu, and Jiri Maly, "What Does d-Wave Symmetry Tell Us About the Pairing Mechanism?" To be published in the Proc. of the 10th Anniv. HTS Workshop on Physics, Materials, and Applications, Houston, TX, March 12-16, 1996 (World Sci., Singapore). James Franck Institute, University of Chicago, Chicago, IL 60637; also available at cond- mat@xxx.lanl.gov (#9605009) and http://rainbow.uchicago.edu/~ldz/paper/paper.html.
Mikael Lindgren, Marc Currie, Carlo Williams, Steven H. Moffat, Robert A. Hughes, Frank A. Hegmann, John S. Preston, Thomas Y. Hsiang, and Roman Sobolewski, "Picosecond Photoresponse of YBa2Cu3O7-x Thin Films." Submitted to the XXI Int. Conf. on Low Temperature Phys. (LT21), Prague, Czech Republic, Aug. 8-14, 1996, to be published in Czechoslovak J. Phys. (1996). Department of Electrical Engineering and Laboratory for Laser Energetics, University of Rochester, Rochester, NY 14627; e-mail lindgren@ee.rochester.edu.
B. Lussier, L. Taillefer, W.J.L. Buyers, T. E. Mason, and T. Peterson, "Influence of a Magnetic Field on the Antiferromagnetic Order in UPt3." Contact Louis Taillefer, Department of Physics, McGill University, 3600 University Street, Montreal, Quebec H3A 2T8, CANADA, telephone (514) 398-6476; telefax (514) 398-6526; e-mail louis@physics.mcgill.ca. Key words: heavy-fermion superconductivity, UPt3, antiferromagnetism. 75.60.-d; 74.25.Ha.
L. Margulies, K. W. Dennis, R. J. Hofer, M. J. Kramer, and R. W. McCallum, "The Effect of Carbon on the Peritectic Melting of Bi2212 and Bi2212+Ag." Submitted to Physica C. Ames Laboratory-USDOE, Iowa State University, Ames, IA 50011-3020; telephone (515) 294-9559; e-mail hanuman@ameslab.gov.
L. Margulies, K. W. Dennis, M. J. Kramer, and R. W. McCallum, "Effect of PO2 and Ag Content on the Decomposition Pathway of Bi2Sr2CaCu2Ox." Submitted to Physica C. Ames Laboratory-USDOE, Iowa State University, Ames, IA 50011-3020; telephone (515) 294-9559; e-mail hanuman@ameslab.gov. Key words: Bi2212, PO2, Ag, phase relations.
A. T. Matveev, J. Ramirez-Castellanos, Y. Matsui, and E. Takayama- Muromachi, "New High-Tc Superconductor, (GezCu1-z)Sr2Ca2-xYxCu3Oy [(Ge,Cu)-1223] Prepared under High Pressure." To be published in Physica C (in press). Contact E. Takayama-Muromachi, National Institute for Research in Inorganic Materials (NIRIM), 1-1 Namiki, Tsukuba, Ibaraki 305, JAPAN.
R. L. Meng, B. R. Hickey, Y. Q. Wang, L. Gao, Y. Y. Sun, Y. Y. Xue, and C. W. Chu, "Fabrication of HgBa2Ca2Cu3O8+d Tape." Preprint #96:056; submitted to the Proc. of the 10th Anniv. HTS Workshop on Physics, Materials, and Applications, Houston, TX, March 12-16, 1996 (World Sci., Singapore). 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.
C. Michel, F. Letouze, C. Martin, M. Hervieu, and B. Raveau, "Neutron Diffraction Structure Determination of the Superconducting Copper Oxychromate Tl3(CrO4)Sr8Cr4O16." To be published in Physica C (in press). Laboratoire CRISMAT, CNRS URA 1318, ISMRA, Universite de Caen, Bd. du Marechal Juin, 14050 Caen Cedex, FRANCE; telefax +33 31 95 16 00.
M. K. Mironova, G. Du, I. A. Rusakova, and K. Salama, "Transmission Electron Microscopy Studies of Low-Angle Grain Boundary Interactions in Melt-Textured YBa2Cu3O7-x." Submitted to Physica C. Preprint #96:0062; Texas Center for Superconductivity, University of Houston, Houston, TX 77204-5932; telephone (713) 743-8200; telefax (713) 743-8201; e-mail mkm3797@jetson.uh.edu or preprints@www.tcs.uh.edu. Key words: coupling, dislocations, flux pinning, grain boundaries, melt texturing.
O. V. Misochko, S. Tajima, C. Urano, H. Eisaki, and S. Uchida, "Raman- Scattering Evidence for Free Spinons in the One-Dimensional Spin-1/2 Chains of Sr2CuO3 and SrCuO2." To be published in Phys. Rev. B (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. 75.50.Lk; 75.10.Nr; 78.30.-j.
C. Paracchini and L. Romano, "The Dissipation of a Superconducting BSCCO Film on the I-T Plane." To be published in Physica C (in press). Dipartimento di Fisica, Universita di Parma, Parma, ITALY.
K. R. Pedersen and J.-E. Jorgensen, "XANES Study of Rare Earth Valency and 4f Hybridization in Pb2Sr2Ln1-xCaxCu3O8 for Ln =Ce, Pr, and Tb." To be published in Physica C. Department of Chemistry, Aarhus University, DK-8000 Aarhus C, DENMARK; telephone +45 8942 3333; telefax +45 8619 6199. Key words: superconductivity, rare-earth valency, 4f hybridization, XANES spectroscopy.
A. K. Pradhan, S. B. Roy, P. Chaddah, D. Kanjilal, C. Chen, and B. M. Wanklyn, "Flux Pinning by Columnar Defects in Bi2Sr2CaCu2O8+y Single Crystals." To be published in Physica C (in press). Low Temperature Physics Group, Centre for Advanced Technology, Indore 452013, INDIA; telefax +91 731-488300 and -481426; e-mail pradhan@cat.ernet.in. 74.30.Ci; 74.60.Ge; 74.60.Mj.
A. K. Pradhan, S. B. Roy, P. Chaddah, D. Kanjilal, C. Chen, and B. M. Wanklyn, "Peak Effect and Magnetization Minima in Bi2Sr2CaCu2O8+y Single Crystals." To be published in Supercond. Sci. & Technol. (in press). Low Temperature Physics Group, Centre for Advanced Technology, Indore 452013, INDIA; telefax +91 731-488300 and -481426; e-mail pradhan@cat.ernet.in.
J. Ramirez-Castellanos, Y. Matsui, T. Kawashima, E. Takayama-Muromachi, and A. E. Kirkland, "Structural Study of Sr3Ca3Cu6O15+-d by HRTEM." To be published in Physica C (in press). Contact Y. Matsui, National Institute for Research in Inorganic Materials (NIRIM), Namiki 1-1, Tsukuba, Ibaraki 305, JAPAN.
A. Rassili and M. Ausloos, "Theory of the Thermal Conductivity of Metallic Localized Spin Compounds in a Magnetic Field." S.U.P.R.A.S., Institut de Physique B5, Universite de Liege, B-4000 Liege, BELGIUM; e- mail rassili@gw.unipc.ulg.ac.be. Key words: thermal conductivity, RE Al2 compounds, variational method, magnetic field, mean-field approximation. 72.15.E; 75.20.Em; 75.30.-m; 75.90.+w.
S. Ratz, R. Boettner, W. Freund, N. Schroeder, S. Marquardt, S. Weiss, M. Guenther, U. Gerhardt, and Th. Wolf, "Angle-Resolved Photoelectron Spectra of YBa2Cu3O7-d (001) Surfaces Prepared with a Micro-Milling Machine." To be published in Physica C, Vol. 261 (in press). Contact U. Gerhardt, Physikalisches Institut der Universitaet, Robert Mayer- Strasse 2-4, D-60054 Frankfurt a. M., GERMANY; telefax +49 69 798 22348.
Z. F. Ren, J. H. Wang, and D. J. Miller, "Superconductivity and Microstructure of Epitaxial TI2Ba2CuO6+d Thin Films." Submitted to Appl. Phys. Lett. Superconductive Materials Laboratory, Department of Chemistry and New York State Institute on Superconductivity, State University of New York at Buffalo, Buffalo, NY 14260-3000; J. H. Wang's telephone (716) 645-6800, ext. 2237; telefax (716) 645-6949.
Marlyse Roulin, Alain Junod, and Eric Walker, "Observation of the Flux Line Lattice Melting Transition in YBa2Cu3O6.94 by Specific Heat Experiments." Submitted to Science. Departement de Physique de la Matiere Condensee, Universite de Geneve, CH-1211 Geneve 4, SWITZERLAND; e-mail marlyse.roulin@sc2a.unige.ch.
Alexandre I. Rykov, Wen-Jye Jang, Hiromi Unoki, and Setsuko Tajima, "Detwinning and Retwinning of YBa2Cu3O7-d Single Crystals with Variable Oxygen Stoichiometry." To be published in the Proc. 8th Int. Symp. on Supercond. (ISS'95), Hamamatsu, Japan, Oct. 30-Nov. 2, 1995. 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.
S. Sathyamurthy, A. S. Parikh, and K. Salama, "Grain Boundary Studies on YBCO Processed by the Liquid Phase Removal Method." Preprint #96:063; submitted to the Proc. of the 16th Int. Cryogenic Eng. Conf. and the Int. Cryogenic Mater. Conf. (ICEC16/ICMC 1996), Kitakyushu, Japan, May 20-24, 1996. 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.
K. Schlenga, G. Hechtfischer, R. Kleiner, W. Walkenhorst, P. Mueller, H. L. Johnson, M. Veith, W. Brodhorb, and E. Steinbeiss, "Subgap Structures in Intrinsic Josephson Junctions of Tl2Ba2Ca2Cu3O10+d and Bi2Sr2CaCu2O8+d." To be published in Phys. Rev. Lett. Physikalisches Institut III, Universitaet Erlangen-Nuernberg, Erwin-Rommel Str. 1, D- 91058 Erlangen, GERMANY; telephone +49 9131 85 7082; telefax +49 9131 15249; e-mail schlenga@physik.uni-erlangen.de. 74.25.Jb; 74.50.+r; 74.80.Dm.
S. A. Sergeenkov, V. V. Gridin, and M. Ausloos, "Influence of a Non- Uniform Current Density Profile on Quasiparticle Excitations and Thermally Activated Flux Creep in YBa2Cu3O7-d." To be published in Z. Phys. B. Contact M. Ausloos, S.U.P.R.A.S., Institut de Physique B5, Sart Tilman, Universite de Liege, B-4000 Liege, BELGIUM; telephone +32 41 66 37 52; telefax +32 41 66 29 90; e-mail ausloos@gw.unipc.ulg.ac.be. 74.50.+r; 74.70.
P. C. Shan, Z. Celik-Butler, D. P. Butler, A. Jahanzeb, C. M. Travers, W. Kula, and Roman Sobolewski, "The Investigation of Semiconducting YBaCuO Thin Films: A New Room Temperature Bolometer." Submitted to J. Appl. Phys. Contact Z. Celik-Butler, Department of Electrical Engineering, Southern Methodist University, P.O. Box 750338, Dallas, TX 75275-0338; telephone (214) 768-3324; telefax (214) 768-3573; e-mail zcb@seas.smu.edu.
B. J. Suh, F. Borsa, D. R. Torgeson, B. K. Cho, P. C. Canfield, D. C. Johnston, J. Y. Rhee, and B. N. Harmon, "Electronics and Magnetic Properties of Single Crystal YNi2B2C from [11]^B and [89]^Y NMR and Magnetic Susceptibility Measurements." Submitted to Phys. Rev. B. Ames Laboratory-USDOE and Department of Physics, Iowa State University, Ames, IA 50011-3020; F. Borsa's e-mail borsa@ameslab.gov. 74.70.Ad; 74.25.Ha; 74.25.Jb; 74.25.Nf.
Holger Szillat, Peter Majewski, and Fritz Aldinger, "Powder Metallurgical Synthesis of YNi2B2C and LuNi2B2C with Superconductivity at 24 K." Submitted to Physica C. Max-Planck-Institut fuer Metallforschung, Pulvermetallurgisches Laboratorium, Heisenbergstr. 5, D-70569 Stuttgart, GERMANY; telefax +49 711 686 1131.
Masakazu Tatsumi, Makoto Kawazoe, and Seika Yamamoto, "Synthesis of Bulk Superconductors RBa2Cu4O8 (R = Tm, Er, Ho, Y, Dy and Gd) by a Simple Solid-State Reaction Method." To be published in Physica C (in press). Department of Applied Chemistry, Faculty of Engineering, Kansai University, Osaka 564, JAPAN.
Jiro Tsujino and Yuh Shiohara, "Growth Process of YBa2Cu3O7-x Films Prepared by rf Thermal Plasma Evaporation." 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.
M. Ullrich, A. Leenders, and H. C. Freyhardt, "Influence of Thermal Cycling on the Levitation Force of Melt-Textured YBaCuO." To be published in Appl. Phys. Lett. Zentrum fuer Funktionswerkstoffe, Windausweg 2, D-37073 Goettingen, GERMANY; telephone +49 551 50717 30; telefax +49 551 50717 50; e-mail ullrich@umpsun1.gwdg.de. Key words: application of superconductors, levitation force thermal cycling, Y1Ba2Cu3O7-d, high-Tc superconductors. 85.25.Ly; 81.40.Rs; 81.40.Np; 74.72.Bk.
N. Vandewalle, M. Ausloos, and R. Cloots, "Fractal Grain Boundaries in Growth Competition." To be published in J. Cryst. Growth. S.U.P.R.A.S., Institut de Physique B5, Universite de Liege, B-4000 Liege, BELGIUM; telephone +32 41 66 37 03; telefax +32 41 66 29 90; e- mail vandewal@gw.unipc.ulg.ac.be. 61.72.Mm; 61.43.Hv; 81.10.Aj; 74.72.- h.
N. Vilalta, F. Sandiumenge, S. Pinol, and X. Obradors, "Precipitate Size Refinement by CeO2 and Y2BaCuO5 Additions in Directionally Solidified YBa2Cu3O7." To be published in J. Mater. Res. Institute de Ciencia de Materials de Barcelona, C.S.I.C., Campus de la UAB, 08193 Bellaterra, SPAIN; e-mail vilalta@icmvax.icmab.es.
Valerii M. Vinokur, M. Cristina Marchetti, and Lee-Wen Chen, "Glassy Motion of Elastic Manifolds." 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.
Y. M. Wan, T. R. Lemberger, S. E. Hebboul, and J. C. Garland, "Transport of High Tc Bi2Sr2CaCu2O8+d Crystals Near the Superconducting Transition." To be published in Phys. Rev. B. Department of Physics, National Tsing Hua University, No. 101, Sec. 2, Kuang Fu Rd., Hsinchu, Taiwan 30043, REPUBLIC OF CHINA; telephone +886 35-715928 or -719037; telefax +886 35 723052; e-mail ymwan@phys.nthu.edu.tw. 74.25.Fy; 74.40.+k; 74.72.Hs.
N. L. Wang, C. Geibel, and F. Steglich, "Observation of Resistivity Saturation Below 300 K in Y-Doped Bi2Sr2CaCu2Oy Single Crystals." To be published in Physica C, Vol. 261 (in press). Institut fuer Festkoerperphysik, Technische Hochschule Darmstadt, Hochschulstrasse 8, D-64289 Darmstadt, GERMANY; telefax +49 6151 164883.
W. G. Wang, J. Horvat, H. K. Liu, and S. X. Dou, "Effect of Mechanical Deformation on Silver/Core Interface and Critical Current Density in Ag/Bi-2223 Single and Multifilament Tapes." Submitted to Supercond. Sci. & Technol. Centre for Superconducting and Electronic Materials, Department of Materials Engineering, University of Wollongong, Northfields Ave., Wollongong NSW 2522, AUSTRALIA; telephone +61 42 214 731; telefax +61 42 214 577; e-mail wgw01@uow.edu.au.
Y.-L. Wang, W. Bian, Y. Zhu, Z.-X. Cai, D. O. Welch, R. L. Sabatini, M. Suenaga, and T. R. Thurston, "A Kinetic Mechanism for the Formation of Aligned (Bi,Pb)2Sr2Ca2Cu3O10 in a Powder-in-Tube Processed Tape." To be published in Appl. Phys. Lett. Department of Applied Science, Brookhaven National Laboratory, Upton, NY 11973.
M. Werner, F. M. Sauerzopf, H. W. Weber, A. Hoekstra, R. Surdeanu, R. J. Wijngaarden, R. Griessen, and K. Winzer, "Comparative Study of Magnetization and Relaxation in YbBa2Cu3O7-d Single Crystals." Submitted to Proc. of Eighth International Workshop on Critical Currents in Superconductors, (8th IWCC), Kitakyushu, Japan, May 27-29, 1996. Atominstitut der OEsterreichischen Universitaeten, A-1020 Vienna, AUSTRIA; e-mail michael@ati.ac.at.
Rachel Wortis and David A. Huse, "Nonlocal Conductivity in the Vortex- Liquid Regime of a Two-Dimensional Superconductor." Submitted to Phys. Rev. B. Department of Physics, University of Illinois at Urbana- Champaign, 1110 West Green Street, Urbana, IL 61801; e-mail rachel@cromwell.physics.uiuc.edu; also available at cond- mat@xxx.lanl.gov (#9604186).
J. Wosik, L. M. Xie, D. Li, J. H. Miller, Jr., and S. A. Long, "Nonlinear Behavior in the Power-Dependent Surface Resistance of High-Tc Superconducting Thin Films: Heating Effects." Preprint #96:055; submitted to the Proc. of the XXI Int. Conf. on Low Temperature Physics (LT 21), Prague, Czech Republic, Aug. 8-14, 1996. 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.
Yasushi Yokoya and Yoshiko Oi Nakamura, "Anomalous Band-Filling Dependence of the Quasiparticle Density of States and the Gap Ratio 2Delta_0/kBTc in Strong-Coupling Superconductors." To be published in Physica C (in press). Department of Applied Physics, Science University of Tokyo, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162, JAPAN. Key words: 2Delta_0/k_BTc, Eliashberg equations, band filling.
N. D. Zakharov, G. Kaestner, D. Hesse, and M. Lorenz, "Observation of Cu Vacancies and Their Ordering in YBa2Cu4O8." Submitted to Appl. Phys. Lett. Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, D-06120 Halle/Saale, GERMANY; G. Kaestner's telephone +49 345 5582-739; telefax +49 345 5511-223; e-mail kaestner@mpi-msp-halle.mpg.de.
Yimei Zhu and J. Tafto, "A Cluster Description of Structural Modulation in Bi2Sr2CaCu2O8+d." Published in Philos. Mag. A, July 1996. Materials Sciences Division, Brookhaven National Laboratory, Upton, NY 11973.
K. Ziegler, M. H. Hettler, and P. J. Hirschfield, "Non-Zero Fermi Level Density of States for a Disordered d-Wave Superconductor in Two Dimensions." Submitted to Phys. Rev. Lett. Max-Planck-Institut fuer Physik Komplexer Systeme, Aussenstelle Stuttgart, Postfach 800665, D- 70506 Stuttgart, GERMANY. 74.25.-q; 74.25.Bt; 74.62.Dh.
*June 13 - 14, 1996: Superconductivity -- Fulfilling Tomorrow's Global Needs, First Symposium of the Educational Institute for Superconductivity (EIS'96), Washington, DC. Purpose is to advance the science and technology of superconductivity and educational applications by providing an educational forum in which representatives from industry, laboratories, universities, and government agencies can exchange ideas and information critical for the development and commercialization of superconductivity applications. The superconductivity industry, its sponsoring agencies, and R&D laboratories will present papers and exhibits focusing on current and future plans, applications, and new technologies. Will include plenary sessions of invited papers on topics related to the development and marketing of products based on low- and high-temperature superconductivity, as well as observations and prospects in the marketplace. Parallel sessions to be held in the following areas: electric power applications, accelerator and fusion applications, electronic applications, and others. For further information, contact Pam Patterson, Conference Manager, Educational Institute for Superconductivity, P.O. Box 178441, San Diego, CA 92177; telephone (619) 490-0164; telefax (619) 490-0138.
*Aug. 2 - 6, 1996: International Conference on Physics and Chemistry of Molecular and Oxide Superconductors (MOS'96), Karlsruhe, Germany. Satellite to the LT21 conf. to be held in Prague, Czech Republic, Aug. 8-14, 1996. MOS'96 is a successor to similar conferences held in Eugene, OR (1993) and Cambridge, U.K. (1990). Topics will include fundamental properties of molecular and oxide superconductors such as cuprate and related compounds, organic superconductors, fullerenes, and borocarbides; normal-state properties; mechanism and theory of superconductivity; synthesis and processing; and new superconducting compounds. Proceedings will be published as a special volume of J. Low Temp. Phys. Program chair: H. Rietschel. Early registration deadline, June 1, 1996. For further information, contact Mrs. E. Maass, MOS'96 Conference Secretary, Institut fuer Nukleare Festkoerperphysik, Forschungszentrum Karlsruhe, Postfach 3640, D-76021 Karlsruhe, Germany; telephone +49 7247 822421; telefax +49 7247 824624. 5/15/96
*Aug. 8 - 14, 1996: XXI International Conference on Low Temperature Physics (LT21), Prague, Czech Republic. Sponsored by the International Union of Pure and Applied Physics. Main topics: quantum fluids and solids, superconductivity, low-temperature properties of solids, techniques, and applications. Proceedings to be published as a special supplement of the Czechoslovak Journal of Physics. For further information, contact the LT21 Office, Low Temperature Laboratory, Institute of Physics ASCR, 250 68 Rez, Czech Republic; telephone and telefax +42 2 6857952; e-mail lt21@fzu.cz. Information also available on anonymous FTP at ftp.fzu.cz server, on WWW in the document http://www.fzu.cz/conferences/LT21.html, and by e-mail server lt21- mserver@fzu.cz.
Sept. 9 - 11, 1996: High Temperature Superconductivity 10, St. Andrews University, St. Andrews, Scotland, UK. Tenth annual meeting in the series. Invited speakers include: J. D. Jorgensen (Argonne), E. Kaldis (ETH Zurich), M. P. Day (The Royal Institution), M. T. Weller (Southampton), S. Lee (St. Andrews), and J. P. Attfield (Cambridge). Oral and poster contributions are solicited on the topics of synthesis, structure, characterization, properties, applications and theory of high-temperature superconductors and related materials. Abstract and registration deadline, June 28, 1996. Cost for registration, lunch, dinner, bed and breakfast from Sept. 9 -11 is 105 pounds, for full participants. For further information contact John T. S. Irvine or P. Lightfoot, School of Chemistry, St. Andrews University, St. Andrews, Fife KY16 9ST; telephone +44 1334 463817; telefax +44 1334 463808; email jtsi@st-and.ac.uk.
*Oct. 21 - 24, 1996: 9th International Symposium on Superconductivity (ISS'96), Sapporo, Hokkaido, Japan. Organized by the International Superconductivity Technology Center (ISTEC). Symposium will consist of oral and poster sessions and invited talks in the following fields of superconductivity: physics -- theory, physical properties, and new measurement techniques; chemistry -- new materials and syntheses, substitution, solid-state chemistry, and properties; flux pinning -- mechanism and electromagnetic properties of fluxoids; wires, tapes, and bulk -- solid-state powder ceramics, chemical-solution processing, melting solidification, and chemical-vapor deposition; thin films -- processing, properties, and lithography; device applications -- digital, analog, SQUID, and other electronic devices; system applications -- power, power transportation, magnets, magnetic shields, and other system applications. Papers are solicited. Abstract deadline, June 30, 1996. Papers will be published. Official language is English. For further information, contact ISS'96 Secretariat, ISTEC, Eishin Kaihatsu Bldg. 6F, 34-3 Shimbashi 5-chome, Minato-ku, Tokyo 105, Japan, telephone +81 3 3431-4002; telefax +81 3 3431-4044; e-mail chyoki@istec.mxa.meshnet.or.jp.
*Dec. 2 - 6, 1996: MRS Fall Meeting: Symposium GG -- High-Temperature Superconductivity - Interplay of Fundamentals and Applications. This symposium will focus on two general problems of interest to both fundamental research and commercial applications: (1) critical currents in bulk high-temperature superconductor materials, and (2) superconductor interfaces in thin-film materials. Goal is also to foster interactions between researchers concerned with problems from both perspectives. Original experimental and theoretical papers in the following topics are requested: vortex structure, pinning, and dynamics; critical currents; wire and tape processing and properties; thin-film growth; heterostructures and interfaces; devices; and applications. Abstract deadline, June 21, 1996. Contact one of the symposium organizers: Charles M. Lieber, Department of Chemistry, Harvard University, 12 Oxford Street, Cambridge, MA 02138; telephone (617) 496-3169; telefax (617) 496-5442 or -6731; e-mail cml@cmliris.harvard.edu; or Ivan Bozovic, MS K-114, Edward Ginzton Research Center, Varian Associates, Inc., 3075 Hansen Way, Palo Alto, CA 94304-1025; telephone (415) 424-6358; telefax (415) 424-6988; e-mail ivan.bozovic@grc.varian.com. Information also available at the MRS homepage http://www.mrs.org.
*Dec. 16 - 21, 1996: International Workshop on High-Temperature Superconductivity: Ten Years After its Discovery, Jaipur, India. Organized by Drexel University, Philadelphia, and University of Rajasthan, Jaipur, and sponsored by the U.S. National Science Foundation. The primary purpose is to bring researchers from India and other countries together to discuss latest developments, to promote dialogue among different groups, and to encourage cooperative activities and international collaborations. The second objective is promotion of science and engineering education focused on the needs of young researchers in the field. Lectures and discussions to be presented by prominent scientists from the U.S. and other countries. Space limitation may restrict number of participants. For further information, contact Workshop Chairs: S. M. Bose, Department of Physics and Atmospheric Science, Drexel University, Philadelphia, PA 19104; telephone (215) 895-1706; telefax (215) 895-4999; e-mail bose@duvm.ocs.drexel.edu; or K. B. Garg, Department of Physics, University of Rajasthan, Jaipur, India; telephone and telefax +91-141- 511912; e-mail cmpl@sirnetd.ernet.in.
*Sept. 14 - 18, 1997: Conference on Spectroscopies in Novel Superconductors (SNS '97), Sea Crest Oceanfront Resort and Conference Center, Falmouth, Cape Cod, MA. Conference sponsored by the College of Arts and Sciences as part of centennial celebration of the founding of Northeastern University. For further information, contact Prof. Arun Bansil, Conference Chair, Dept. of Physics, Northeastern University, Boston, MA 02115; telephone (617) 373-2923; telefax (617) 373-294 or Julie Pumphrey, Conference Secretary, The Barnett Institute, Northeastern University, Boston, MA 02115; telephone (617) 373-2868; telefax (617) 373-2855.
An electronic publications catalog has been added to the TMS Online World Wide Web service. The In-Print Internet bookstore provides access to over 150 society-published titles and supplies current information on recently published titles, book sales, and upcoming publications. Subject index and search capabilities included. URL is http://www.tms.org/pubs/books/books.html. Contact Dan Steighner, TMS, 420 Commonwealth Drive, Warrendale, PA 15086-7514; telephone (412) 776- 9000, ext. 210; telefax (412) 776-3770; e-mail steighner@tms.org.
You can extract information on how to subscribe to the newsletter and submit preprints, and can browse through the current issue and back issues of the newsletter. You can also search the newsletters for keywords, authors, etc.
In addition, High-Tc Update is available electronically as an ASCII file or as coded Word files from an anonymous ftp site. To download electronic versions of the newsletter, please follow the procedure below:
ftp hightc.ameslab.gov USERNAME: anonymous PASSWORD: [your username] cd pub get filename.extThe file names are, for example, 96jun1.rtf (for RTF version), 96jun1.hqx (for BINHEX version), and 96jun1em.txt (for ASCII version). Coded Word files are available at this site from Nov. 15, 1993 issue; ASCII files are available from Jan. 1992 to the present issue.
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, #11, June 1, 1996.