HIGH-Tc UPDATE E-MAIL VERSION, VOL. 13, NO. 14, July 15, 1999.
<p>
 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, and other
 agencies, organizations, and individuals.
 <hr>
<p>
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<p>
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<p>
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<p>
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<p>
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 are left as they appear: Tc, Jc, YBa2Cu3O7, O2. Mu-m is changed to
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 <hr>
<p>
 NOTA BENE:
<p>
 Vortices
<p>
 The magnetic-field dependence of the Josephson plasma resonance (JPR)
 frequency in pristine and in irradiated Bi2Sr2CaCu2O8+d (Bi-2212)
 crystals near Tc is theoretically examined in a preprint by L. N.
 Bulaevskii (Los Alamos) et al. For low magnetic fields along the c axis
 in the single-vortex regime, the authors calculate linear in-field
 corrections to the plasma frequency due to thermal wiggling of vortex
 lines by accounting for both Josephson and magnetic interlayer coupling
 of pancake vortices. These corrections, which are similar in solid and
 liquid vortex phases, are in agreement with experimental data. This
 provides evidence that at low fields, near Tc, the vortex-solid phase
 melts into a liquid of vortex lines. The authors find that pinning by
 columnar defects only weakly affects the field dependence of the plasma
 frequency near Tc.
<p>
 In a related paper by A. E. Koshelev (Argonne) and L. N. Bulaevskii (Los
 Alamos), the authors calculate the shape of the Josephson plasma
 resonance line due to thermal fluctuations. The authors find that the
 broadening of the line is strongly asymmetric, in agreement with
 experimental observations. The authors also show that the relative
 linewidth is determined by the parameter (k_B)T/E_0, where E_0 =
 s(phi)_0^2/16(pi)^3[lamda_(ab)]^2 is the in-plane phase stiffness.
<p>
 Dynamic and thermodynamic magnetization experiments on heavy-ion
 irradiated single-crystalline Bi-2212 have been correlated by C. J. van
 der Beek (Ecole Polytechnique) et al. to clarify the nature of the
 mixed-state phase diagram. The authors find that whereas the entropy
 contribution to the free energy in the London regime plays a minor role
 in unirradiated crystals and in irradiated crystals close to or above
 the matching field B_[phi], it becomes very important at low fields in
 irradiated crystals with high B_[phi]. Direct determination of the
 entropy contribution to the free energy from the reversible
 magnetization allows one not only to determine the correct values of the
 pinning energy, but also to extract detailed information about pancake-
 vortex alignment.
<p>
 A preprint by M. Takigawa et al. (Okayama) reports a theoretical study
 of the temperature dependence of the site-dependent nuclear spin-lattice
 relaxation time T_1 near vortices in s-wave and d-wave superconductors.
 Because of low-energy electronic excitations associated with the vortex
 core, the temperature dependence deviates from the zero-field behavior,
 and (T_1)^[-1] is enhanced in the vortex core, where it has a new peak
 below Tc. The authors suggest that experimental NMR studies of this
 field dependence may provide a means of spatially resolving the vortex-
 core structure.
<p>
<p>
 Microwave Microscopy
<p>
 Three preprints by A. F. Lann (Hebrew University of Jerusalem) et al.
 describe devices for carrying out high-resolution near-field mm-wave
 microscopy. One of these describes a vacuum cryogenic (80 K < T < 350
 K) near-field microwave scanning system based on a 90 GHz
 transmitting/receiving resonant slit antenna with a capacitive
 measurement of the probe-sample separation. The probe allows local
 measurements of resistance as a function of temperature with a spatial
 resolution of 20-50 micrometers. A second preprint reports local
 studies of magnetic-field-modulated microwave reflectivity (MFMMR) of
 high-Tc superconductors using a near-field scanning aperture probe
 operating at 96 GHz with a spatial resolution of 250 micrometers. The
 third paper describes a similar instrument, which is capable of
 performing local polarization-sensitive measurements with a spatial
 resolution of 180 micrometers. The authors suggest that this method may
 be useful for mapping Hall mobilities in semiconductors.
<p>
<p>
 RBa2Cu3O7-d
<p>
 The effects of (Nd0.33Eu0.33Gd0.33)2BaCuO5 (NEG-211), Gd2BaCuO5 (Gd-
 211), and Pt additions on melt-processed (Nd0.33Eu0.33Gd0.33)Ba2Cu3O7-d
 (NEG-123) composites have been investigated by M. Muralidhar et al.
 (SRL-ISTEC) using a combination of transmission electron microscopy
 (TEM) and measurements of the critical current density Jc. TEM
 observations reveal the presence of submicron-size 211 particles, which
 lead to enhancements of Jc in both low and high fields. For NEG-123
 with additions of 40 mol% NEG-211 and 0.5 mol% Pt, the Jc was 7 x 10^4
 A/cm^2 at 77 K for a 2.2 T field applied along the c axis. Similar
 results are reported in a related paper by M. Muralidhar and M. Murakami
 (SRL-ISTEC).
<p>
 NMR studies of the effect of substitutional impurities in the CuO2
 planes of the cuprates, especially YBa2Cu3O7-d, have been carried out by
 H. Alloul et al. (Orsay). The authors find that the pseudogap in the
 underdoped regime is unmodified far from the impurities even though Tc
 is greatly reduced. The NMR measurements also demonstrate that
 nonmagnetic impurities such as Zn induce local-moment behavior on
 neighboring Cu sites.
<p>
 Using thermal analysis and neutron powder diffraction, D. G. Hinks
 (Argonne) et al. have investigated the products of the reaction of
 reduced YBa2Cu3O6+x with Br. The authors find that although Br is not
 intercalated into the 123 structure, the reaction reduces the 123
 particle size, allowing oxygen formed at the reacting surface to diffuse
 into the material in a reasonable time scale at the low reaction
 temperatures to produce nanoscale YBa2Cu3O7.
<p>
 High-energy x-ray diffraction has been used by M. v. Zimmermann
 (HASYLAB) et al. to investigate the bulk oxygen ordering properties of
 YBa2Cu3O6+x. Superstructures of CuO chains aligned along the b axis and
 ordered with periodicity ma (m = integer) along the a axis were
 observed. For x < 0.62, the only observed superstructure is ortho-II
 with m = 2. At room temperature the authors find ortho-III (m = 3) for
 0.72 <= x <= 0.82, ortho-V (m = 5) in a mixed state with ortho-II at x =
 0.62, and ortho-VIII (m = 8) at x = 0.67. The authors find that ortho-
 II is a 3D ordered structural phase, while the remaining ones are
 essentially 2D.
<p>
 The temperature dependence of the fish-tail or second magnetization peak
 H_p(T) in a deoxygenated single crystal of YBa2Cu3O6.65 with Tc = 62.5 K
 has been measured by S. Salem-Sugui, Jr. (Rio de Janeiro) et al. The
 peak was observed from 60 K down to 1.8 K. For 6 K < T < 60 K, H_p(T)
 was found to increase with a positive curvature as the temperature was
 lowered, while for T < 6 K, H_p(T) varied linearly with temperature,
 with an extrapolated value H_p(0) = 2.9 T. Magnetic relaxation
 measurements for fields near the second magnetization peak indicate a
 change in the mechanism for this peak for T < 5 K: At higher
 temperatures the peak position changes with time, while for temperatures
 below 5 K there is no difference in relaxation above and below H_p, and
 the position of the peak does not change with time.
<p>
 Single-domain YBa2Cu3O7-d (YBCO) bulk superconductors with a high
 levitation force (70 N) have been fabricated by W. M. Yang (NINMR-Xi'an,
 Jena, and Shenyang) et al. using a modified melt-textured-growth
 process. The sample was cut into a group of small rectangular samples
 with the same dimensions, 3.5 x 3.5 x 5 mm^3, but with different grain
 orientations. The authors found that the levitation force decreased
 monotonically from theta = 0 to 90 degrees, where theta is the angle
 between the c axis and the normal to the polished surfaces. To
 explain the data, the authors employed a critical-state model that
 accounts for the different critical current densities Jc^[ab] and Jc^[c]
 along the ab and c directions.
<p>
<p>
 Bi Cuprates
<p>
 Using angular resolved photoemission, R. Gatt (Wisconsin-Madison) et al.
 have measured the angular dependence of the superconducting gap in
 highly overdoped Bi2Sr2CaCu2O8+d (Bi-2212, Tc = 65 K). While the node
 at 45 degrees is preserved, the authors found substantial deviations
 from a first-order d-wave (cos2phi) dependence away from the node. The
 authors found that the pairing susceptibility is peaked at special
 regions on the Fermi surface. Using a detailed mapping of the Fermi
 surface for this doping range, the authors measured the nominal hot-spot
 location and the extension of the hot regions, which were found to be
 evenly spread about the nominal locations of the hot spots. The
 decrease of the gap amplitude away from these hot spots closely follows
 theoretical calculations within the spin-fluctuation approach. From a
 fit to these calculations, the authors extracted the magnetic
 correlation length and found it to be in good agreement with what is
 expected for the highly overdoped region of the phase diagram.
<p>
 Magnetic measurements by L. Ghivelder (Rio de Janeiro) et al. in the
 vicinity of the irreversibility line show evidence for a field-induced
 dimensional crossover in the vortex ensemble in (Bi,Pb)2Sr2Ca2Cu3O10+d
 [(Bi,Pb)-2223]. From both dc magnetization and ac susceptibility
 measurements, the authors found that the temperature dependence of the
 irreversibility line changed its behavior at a crossover field H_[cross]
 = (3.0+-0.5) kOe, independent of the ac field amplitude and frequency.
 Identifying this crossover field with the corresponding expression
 H_[cross] = phi_0/[gamma^2s^2] given by L. I. Glazman and A. E.
 Koshelev [Phys. Rev. B 43, 2835 (1991)], where gamma =
 lamda_c/lamda_[ab] and s is the spacing between adjacent groups of CuO2
 layers, the authors estimate gamma = 45+-5 for (Bi,Pb)-2223.
<p>
<p>
 Other Cuprates
<p>
 The effects of thallium and mercury content x on properties of as-
 sintered and post-annealed samples of MxPb0.4Sr1.6Ba0.4Ca2Cu3O8+d [M =
 Tl (0.32 <= x <= 0.74) or Hg (0.18 <= x <= 0.68)] have been studied by
 A. Cigan (Bratislava) et al. using magnetization and transport
 measurements. For Tl-1223, the authors found the optimum Tl doping
 level to be x = 0.53 with respect to the grain properties,
 superconducting phase content, first penetration field, transport
 critical current density, magnetic intergrain critical current density,
 and intragrain critical current density. The critical temperature Tc of
 the as-sintered Tl-1223 samples decreased with increasing Tl content.
 Post-annealing in oxygen improved the Tc for Tl content x >= 0.53 and
 had generally positive effects on the critical current densities. The
 intergrain properties of the Hg-1223 samples were much worse than those
 of the Tl-based superconductors.
<p>
 A preprint by P. M. Singer et al. (MIT) demonstrates that the integrated
 intensity of the [63]^Cu nuclear quadrupole resonance (NQR) in La1.6-
 xNd0.4SrxCuO4 decreases dramatically below the charge-stripe ordering
 temperature T_[charge]. Comparison with neutron and x-ray scattering
 indicates that the wipeout fraction F(T) (the missing fraction of the
 integrated intensity of the NQR signal) represents the charge-stripe
 order parameter. The authors' systematic study reveals bulk charge-
 stripe order throughout the superconducting region 0.07 <= x <= 0.25.
 As a function of the reduced temperature t identical to T/T_[charge],
 the temperature dependence of F(t) is sharpest for the hole
 concentration x ~ 1/8, indicating that x ~ 1/8 is the optimum
 concentration for stripe formation. The authors also find that the
 superconductivity phase boundary exists within the charge-stripe phase
 boundary, indicating that stripes and superconductivity can and do
 coexist.
<p>
 Using [63]^Cu NQR, K. R. Thurber (MIT) et al. have probed spin-spin
 correlations up to 725 K in the S = 1/2 three-leg ladder compound
 Sr2Cu3O5. The authors present experimental evidence that below 300 K,
 weak interladder coupling causes dimensional crossover of the spin-spin
 correlation length xi from a quasi-1D (xi proportional to 1/T) to an
 anisotropic 2D regime [xi proportional to exp[2(pi)(rho)_s/T], where
 2(pi)(rho)_s = (290+-30) K is the effective spin stiffness]. The
 authors assert that this is the first experimental verification of the
 renormalized classical behavior of the anisotropic nonlinear sigma model
 in 2D, which recently has been proposed for the striped phase in high-Tc
 cuprates.
<p>
<p>
 Films
<p>
 Two preprints listed in this issue report progress at Los Alamos
 National Laboratory in the development of YBCO coated conductors
 deposited by pulsed-laser deposition (PLD) over buffer layers on
 biaxially aligned MgO template films prepared by ion-beam-assisted
 deposition (IBAD). J. R. Groves (Los Alamos) et al. report that IBAD
 MgO films (thickness ~10 nm) were deposited by e-beam evaporation on
 strips of polished Haynes 242 and Inconel 625 nickel-based alloys. A
 homoepitaxial deposition of another 80 nm of MgO was then added to
 provide sufficient thickness for the MgO texture to be quantified by x-
 ray diffraction. The resulting in-plane textures, measured by x-ray phi
 scan, had full width at half maximum (FWHM) between 11 degrees and 15
 degrees. Additional buffer layers [50 nm of yttria-stabilized zirconia
 (YSZ) followed by 20 nm of yttria] were deposited by PLD. YBCO films
 about 1 micrometer thick were then deposited by PLD. The YBCO phi-scan
 FWHM values tended to improve over those of the MgO templates by 1-2
 degrees. The YBCO transition temperatures ranged from 87 K to 90 K,
 with transition widths of about 0.5 K. The best superconducting
 transport properties measured on these YBCO films included an I_c = 41.6
 A (75 K, self-field, 1cm width) and a narrow-bridge Jc = 0.46 MA/cm^2
 for a film of thickness 1.35 micrometer.
<p>
 A preprint by J. R. Groves et al. (Los Alamos) notes that the above Jc
 of 0.46 MA/cm^2 was lower than desired, in part because of roughness of
 the metal substrate. In an effort to demonstrate large Jc values using
 IBAD MgO as a template, the authors in this next paper used smoother,
 commercially polished single-crystal and polycrystalline YSZ for the
 substrates. A layer of amorphous silicon nitride (Si3N4, thickness 50
 nm) was deposited at room temperature by e-beam evaporation on the YSZ
 substrates to ensure that no substrate registry would influence the IBAD
 or subsequent heteroepitaxial buffer layers and YBCO film depositions.
 Ar^+ ions (kinetic energy 900 eV) were then used during the deposition
 of IBAD MgO to a thickness of ~10 nm. The Ar ion source was turned off
 and an e-beam source of MgO was used to deposit an additional ~90 nm of
 MgO. The samples were then transferred to the PLD system, where SrTiO3
 buffer layers (~200 nm thick) and YBCO layers (~500 nm thick) were
 deposited. Microbridges were patterned into the YBCO films prior to
 measuring the YBCO critical current densities. The authors show a phi
 scan of the (103) diffraction peak for a YBCO film in the architecture
 YBCO/SrTiO3/MgO/ IBAD MgO/Si3N4/YSZ with a FWHM value of 2.1 degrees,
 for which the narrow-bridge, self-field Jc at 75 K was 3.1 MA/cm^2
 (thickness 440 nm). The authors conclude that to obtain good
 crystallographic texture in the IBAD MgO and subsequent heteroepitaxial
 films, the substrate surface roughness must be extremely low. The next
 logical step for this work is to achieve similar high Jc values using
 polycrystalline metal substrates for the deposition platform.
<p>
 Segregation and competition of Y-based impurities in Y-rich biepitaxial
 YBCO samples have been investigated by U. Scotti di Uccio (INFM-Napoli)
 et al. Using high-resolution electron microscopy, the authors found
 Y2O3 precipitates in (103) YBCO films grown on (110) SrTiO3 substrates.
 On the same biepitaxial samples, Y2BaCuO5 (Y-211) precipitates were
 found on (001) YBCO films deposited on an intermediate (110) MgO seed
 layer.
<p>
 An optical study of the superconducting transition in YBa2Cu3O7-d films
 on MgO substrates has been carried out by O. V. Misochko (KARC-Iwaoka
 and Chernogolovka) et al. using femtosecond pump-probe spectroscopy. In
 both the normal and superconducting states, the authors observed the
 transient time-resolved reflectivity caused by oscillations associated
 with two A_[1g] metal-ion modes. The temporal interference between the
 modes was found to be modified below the phase transition, which also
 results in an altered relative intensity of the modes in the Fourier
 transformed spectra.
<p>
<p>
 Applications
<p>
 A numerical method for solving for the current and field distributions
 inside devices containing type-II superconductors is described in a
 preprint by G. Barnes et al. (Oxford). The two-dimensional solution
 technique accounts for the effects of surrounding media, including iron,
 and can handle systems with an arbitrary number of superconducting and
 conventional materials. The technique is based on the finite-element
 method, the method of moments, and the critical-state model. The
 impetus behind this work is the study of rotating electrical machines
 that contain superconducting components as well as magnetic materials
 and current sources. In this paper, a reluctance machine consisting of
 an iron rotor flanked by two high-temperature superconductors is chosen
 to demonstrate the method.
<p>
 As shown by A. Blais (Sherbrooke) and A. M. Zagoskin (Sherbrooke and
 UBC), a solid-state superconducting quantum computer based on clean
 Josephson junctions between d-wave superconductors allows application of
 the complete set of quantum logical gates and is therefore a realization
 of a universal quantum computer.
<p>
 A preprint by S. Inoue et al. (Toshiba) reports on the properties of
 YBa2Cu3O7-d/PrBa2Cu3O7-d/YBa2Cu3O7-d ramp-edge Josephson junctions
 and their current-voltage (I-V) characteristics. The authors made dc
 SQUIDs from these junctions. They also fabricated a SQUID-based
 flip-flop circuit and confirmed both flux trapping and flux detrapping
 when 1 ms current pulses were injected into the SQUID loop.
<p>
 A comprehensive analytical theory of nonhysteretic rf SQUIDs operating
 in the adiabatic mode at temperatures around and above 77 K has been
 developed by B. Chesca (Juelich and Augsburg). When beta << 1 [beta =
 2(pi)LI_c/phi_0 = hysteresis parameter], the theory also is applicable
 to rf SQUIDs operating in the nonadiabatic mode. In contrast to
 previous theories that apply only if [beta x Gamma] << 1 (the case of
 small thermal fluctuations at 4.2 K), where Gamma is the noise
 parameter, the present theory is valid for [beta x Gamma] around unity
 or higher (the case of large thermal fluctuations at 77 K). The author
 finds good qualitative agreement with experiment. Based on this
 analytical investigation, the author predicts that the energy sensitivity
 of an rf SQUID should be superior to that of a dc SQUID at 77 K and
 at frequencies below 0.5 Hz.
<p>
 A new process for making high-temperature superconducting multilayer
 circuits is reported in a paper by H. Q. Li (NIST-Boulder) et al.
 Proximity exposure is used to form controllable shallow edges, which are
 required for crossovers and interconnects. Small features with shallow
 edges can be achieved by a combination of contact exposure and proximity
 exposure. Using this process, the authors prepared stacked YBCO
 Josephson junctions on SrTiO3 bicrystal substrates and fabricated a
 multilayer low-inductance dc SQUID showing large voltage modulation (100
 microvolts peak-to-peak voltage at 62 K).
<p>
 A paper by S. Y. Lee (Konkuk) et al. reports the microwave properties of
 devices fabricated from YBa2Cu3O7-d films grown on (100) LaAlO3 (LAO),
 (110) NdGaO3 (NGO), and (001) SrLaAlO4 (SLAO) substrates. A YBCO
 resonator on an SLAO substrate exhibited microwave properties better
 than or comparable with YBCO resonators on LAO substrates. The authors
 also demonstrated an X-band oscillator with a YBCO ring resonator as the
 resonant element.
<p>
<p>
 Theory
<p>
 As described in a preprint by M. E. Simon and C. M. Varma (Bell Labs),
 the authors have used a variational method to solve the problem of a
 magnetic impurity in a d_[x^2-y^2]-wave superconductor. A moment is
 found to exist in the superconducting state only if the Kondo
 temperature in the normal state is larger than the maximum in the
 superconducting gap function. If a moment exists in the superconducting
 state and the spin-orbit coupling is nonzero, the moment induces,
 locally around the impurity, a time-reversal-breaking superconducting
 state which is a linear combination of d_[x^2-y^2] and d_[xy] states.
 The authors also calculated the current pattern around the impurity.
<p>
 The c-axis quasiparticle conductivity sigma_q in highly anisotropic,
 Josephson-coupled layered compounds in the presence of a magnetic field
 parallel to the layers has been examined theoretically by L. N.
 Bulaevskii et al. (Los Alamos). The authors show that at low
 temperatures the quasiparticle interlayer conductivity depends strongly
 on the orientation of the in-plane magnetic field if the excitation gap
 has nodes on the Fermi surface. Measurements of the angle-dependent c-
 axis (out-of-plane) magnetoresistance as a function of the orientation
 of the in-plane component of the magnetic field thus provide information
 on the momentum dependence of the superconducting gap or pseudogap on
 the Fermi surface. Clean and highly anisotropic layered superconductors
 seem to be the best candidates for probing the existence and location of
 the nodes on the Fermi surface.
<p>
 As noted in a preprint by P. D. Sacramento (Lisboa), there are two
 contributions to the Hall conductance in the superconducting state, one
 due to vortex motion and the other due to quasiparticles. In this paper
 the author calculates the quasiparticle contribution to the Hall
 conductance when the vortex lattice is rigidly pinned. The author uses
 the Kubo formula and the solution of the Bogoliubov-de Gennes equations
 for the wave function amplitudes expanded in the Landau basis.
<p>
 The doping dependence of the parameters of the cold-spot model of charge
 transport in the cuprates has been studied by R. Hlubina (Comenius).
 The author argues that a recently proposed test of the in-plane
 anisotropy of charge transport by carrying out a nonlinear conductivity
 experiment should be feasible in underdoped cuprates, where electric
 fields of the order of 10 V/cm should be sufficient to perform the test.
<p>
 Using generalized coherent states to analyze the SO(5) theory of high-
 temperature superconductivity and antiferromagnetism, L.-A. Wu (Jilin)
 et al. demonstrate that the SO(5) symmetry can be embedded in a larger
 algebra that allows it to be interpreted as a critical dynamical
 symmetry interpolating between antiferromagnetic and superconducting
 phases. The dynamical interpretation suggests that SO(5) defines a
 phase with the character of a spin glass for a significant range of
 doping.
<p>
 A preprint by P. V. Shevchenko (New South Wales) et al. theoretically
 treats the double-layer Heisenberg antiferromagnet at finite temperature
 using two complementary approaches: an analytical Brueckner
 approximation and numerically exact quantum Monte Carlo simulations.
 The authors calculate the temperature-dependent spin excitation spectrum
 (including the triplet gap), dynamic and static structure factors, the
 specific heat, and the uniform magnetic susceptibility, and they find
 excellent agreement between the analytical and numerical approaches.
<p>
 First-principles cluster calculations of the electronic structure of
 La2CuO4 have been carried out by P. Huesser et al. (Zurich). Several
 clusters containing up to nine copper atoms embedded in a background
 potential were investigated. The authors provide a detailed analysis
 that compares the hyperfine fields obtained for various cluster sizes
 with results from additional calculations of spin states with different
 multiplicities. The authors conclude that hyperfine couplings are
 mainly transferred from nearest-neighbor Cu^[2+] ions and that
 contributions from more distant neighbors are very small.
<p>
 The attractive Hubbard model in d = 2 has been studied by S. Allen
 (Sherbrooke) et al. using Monte Carlo simulations at intermediate
 coupling. The authors find a crossover temperature T_X where a
 pseudogap appears with concomitant precursors of Bogoliubov
 quasiparticles that are not local pairs. The pseudogap in A(k_F,omega)
 occurs in the renormalized classical regime when the correlation length
 is larger than the direction-dependent thermal de Broglie wave length
 xi_[th] = h[bar]v_F(k)/(k_B)T.
<p>
 A preprint by N. Andrenacci et al. (Camerino) describes a theoretical
 treatment of a system of fermions in the continuum case at zero
 temperature in the strong-coupling limit of a short-range attraction
 when composite bosons form as bound fermion pairs. The authors examine
 the density dependence of the size of the composite bosons to leading
 order in the density (the dilute limit) and show on general physical
 grounds that this size should decrease with increasing density in both
 two and three dimensions.
<p>
 The scaling behavior in the critical domain of superconductors in zero
 external magnetic field is theoretically considered in a preprint by C.
 de Calan and F. S. Nogueira (Ecole Polytechnique). The authors
 interpret a recent experiment by K. M. Paget et al. [Phys. Rev. B 59,
 6545 (1999)] in YBa2Cu3O7-d thin films. The authors argue that the
 measured mean-field-like behavior of the penetration-depth exponent nu'
 is possibly associated with a nontrivial critical behavior. The authors
 predict the exponents nu = 1 and alpha = -1 for the correlation length
 and the specific heat.
<p>
 As reported by K. Machida (Okayama) et al., the orbital symmetry of the
 superconducting order parameter in UPt3 has been identified by
 theoretically evaluating the directionally dependent thermal
 conductivity and ultrasound attenuation in the clean limit, and
 comparing with the existing data along the basal plane and the c axis of
 a hexagonal crystal. However, how the orbital part combines with the
 spin part is still in question, the possibilities being a nonunitary
 bipolar state and a unitary planar state. The authors propose
 experiments to distinguish between these two states.
<p>
 A quantitative theory of Cooper pair pumping in gated one-dimensional
 arrays of Josephson junctions has been developed by J. P. Pekola
 (Jyvaskyla) et al. The pumping accuracy is limited by quantum tunneling
 of Cooper pairs out of the propagating potential well and by direct
 supercurrent flow through the array. Both corrections decrease
 exponentially with the number of junctions in the array but seriously
 limit the accuracy for any practical array.
<p>
<p>
 Other Activities
<p>
 The position of the central (low-field) peak in magnetization hysteresis
 loops has been analyzed by M. R. Koblischka (Oslo and SRL-ISTEC) in
 various high-Tc superconducting samples, including several RBa2Cu3O7-d
 (R = rare earth) single crystals of different thicknesses, a laser-
 ablated YBa2Cu3O7-d thin film, Ag-sheathed (Bi,Pb)2Sr2Ca2Cu3O10+d
 [(Bi,Pb)-2223] mono- and multifilamentary tapes, and a model sample
 designed to reproduce a layer of grains. The single crystals and the
 thin film showed the peak at zero field or at negative applied fields on
 the descending-field branch, in accord with critical-state models, while
 the (Bi,Pb)-2223 tapes exhibited the peak anomalously in positive
 applied fields. Local magnetic field distributions in applied fields
 close to zero, studied using magneto-optical techniques, showed that the
 large demagnetizing effect in perpendicular geometry facilitates the
 penetration of vortices of opposite polarity along structural defects,
 forcing the central peak toward zero or even to small positive fields.
 Granularity in the (Bi,Pb)-2223 tapes leads to an additional shift of
 the peak toward positive fields.
<p>
 Using resistance measurements along the Tc(H) line of regular arrays of
 nanofabricated micron-size holes in superconducting Al films, C. C.
 Abilio (Grenoble) et al. have found a rich field structure due to the
 interference of superconducting states nucleated at the edges of the
 holes. Comparisons using different hole shapes show the influence of
 the geometry of the arrays, which can be described either as
 superconducting wire networks or as weak-link arrays.
<p>
<p>
 Overviews
<p>
 The growth of Bi2Sr2Can-1CunOy and infinite-layer (Sr,Ca)mCunOy thin
 films by molecular beam epitaxy (MBE) is reviewed in a paper by D. J.
 Rogers et al. (Wintici R&D Centre). The authors outline what needs to
 be done to grow cuprate superconductors in an MBE system, and they
 discuss six critical parameters that must be optimized for successful
 growth: (1) source temperature (or cation flux), (2) shutter timing,
 (3) oxidant pressure, (4) oxidant turn-off temperature, (5) substrate
 material, and (6) substrate temperature (72 refs.).
<p>
 The current status of basic research related to the understanding and
 development of coated conductor tapes for use in large-scale
 superconducting applications is described in a summary article by D. K.
 Finnemore (Ames Lab, Iowa State) et al. The paper reports highlights of
 a workshop and discussion meeting that dealt with many of the central
 issues associated with thick-film deposition and the defects that
 control the critical current density (no refs.).
<p>
 Contributed by John R. Clem
<p>
 <hr>
<p>
 Contents: Preprints begin on page 6 and Coming Events are on page 13.
<p>
<p>
 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.
<p>
 <hr>
<p>
 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.
<p>
 C. C. Abilio, L. Amico, Rosario Fazio, and B. Pannetier, "Coherence
 Between Superconducting Edge States in Superconducting Periodic Arrays
 of Artificial Defects." Submitted to J. Low Temp. Phys. Centre de
 Recherches sur les Tres Basses Temperatures, Laboratoire associe a
 l'Universite Joseph Fourier, CNRS, 25 Av. des Martyrs, BP 166, F-38042
 Grenoble Cedex 9, FRANCE; telephone +33 4 7688 1226; telefax +33 4 7687
 5060; e-mail <a href="mailto:abilio@labs.polycnrs-gre.fr">abilio@labs.polycnrs-gre.fr;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9905366">http://xxx.lanl.gov/abs/cond-mat/9905366.</a> 74.76.-w; 74.60.Ge; 74.25.Dw.
<p>
 V. C. Aguilera-Navarro, M. de Llano, and M. A. Solis, "Bose-Einstein
 Condensation for General Dispersion Relations." To be published in Eur.
 J. Phys. (in press). Contact M. A. Solis, Instituto de Fisica,
 Universidad Nacional Autonoma de Mexico, Apdo. Postal 20-364, 01000
 Mexico DF, MEXICO; e-mail <a href="mailto:masolis@fenix.ifisicacu.unam.mx">masolis@fenix.ifisicacu.unam.mx.</a> Key words:
 Bose-Einstein condensation, phase transition, thermodynamic properties.
 03.75.Fi; 05.30.Jp; 67.40.Kh.
<p>
 S. Allen, H. Touchette, S. Moukouri, Y. M. Vilk, and A.-M.S. Tremblay,
 "The Role of Symmetry and Dimension on Pseudogap Phenomena."
 Departement de Physique and Centre de Recherche en Physique du Solide,
 Universite de Sherbrooke, Sherbrooke, Quebec, CANADA J1K 2R1; A.-M.S.
 Tremblay's e-mail <a href="mailto:tremblay@physique.usherb.ca">tremblay@physique.usherb.ca;</a> preprint also available
 at <a href="http://xxx.lanl.gov/abs/cond-mat/9904436">http://xxx.lanl.gov/abs/cond-mat/9904436.</a> 71.10.Fd; 71.10.Pm;
 71.10.Hf; 74.20.Mn.
<p>
 H. Alloul, J. Bobroff, A. Mahajan, P. Mendels, and Y. Yoshinari, "NMR
 Studies of the Original Magnetic Properties of the Cuprates: Effect of
 Impurities and Defects." To be published in High Temperature
 Superconductivity: AIP Proc. of the Univ. of Miami Conf. on High Temp.
 Supercond. (HTS99), Miami, Fla., Jan. 7-13, 1999. Laboratoire de
 Physique des Solides, UMR 8502 CNRS, Universite Paris-Sud, F-91405 Orsay
 Cedex, FRANCE; e-mail <a href="mailto:alloul@lps.u-psud.fr">alloul@lps.u-psud.fr;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9905424">http://xxx.lanl.gov/abs/cond-mat/9905424.</a>
<p>
 N. Andrenacci, P. Pieri, and G. C. Strinati, "Size Shrinking of
 Composite Bosons for Increasing Density in the BCS to Bose-Einstein
 Crossover." Dipartimento di Matematica e Fisica, Sezione INFM,
 Universita di Camerino, I-62032 Camerino, ITALY; e-mail
 <a href="mailto:pieri@str.unicam.it">pieri@str.unicam.it;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9906115">http://xxx.lanl.gov/abs/cond-mat/9906115.</a> 74.20.Fg; 74.25.-q; 74.20.Mn;
 74.20.-z.
<p>
 Anjana Asthana and O. N. Srivastava, "The Synthesis, Characterization
 and Effect of Ag Doping on the Transition Temperature and Critical
 Current Density of Hg1-xPbxBa2Ca2Cu3O8+d (0.1 <= x <= 0.5) HTSC Tapes."
 To be published in Physica C (in press). Contact O. N. Srivastava,
 Department of Physics, Banaras Hindu University, Sampoornanand Nagar,
 Sigra, Varanasi 221 005, INDIA; telephone +91 542 36 1937; telefax +91
 542 31 7468; e-mail <a href="mailto:banaras@ernet.in">banaras@ernet.in.</a> Key words: HTSC tapes,
 transition temperature, critical current density.
<p>
 Gary Barnes, Malcolm McCulloch, and David Dew-Hughes, "Computer
 Modeling of Type II Superconductors in Applications." Submitted to
 Supercond. Sci. & Technol. Department of Engineering Science T1,
 University of Oxford, Parks Road, Oxford OX1 3PJ, UNITED KINGDOM;
 telephone +44 1865 273000; e-mail <a href="mailto:gary.barnes@eng.ox.ac.uk">gary.barnes@eng.ox.ac.uk.</a> 74.60.-w;
 74.25.Ha; 07.05.-t; 02.60.Cb; 02.70.Dh.
<p>
 E. V. Bezuglyi, E. N. Bratus, V. S. Shumeiko, and G. Wendin, "Multiple
 Andreev Reflections and Enhanced Shot Noise in Diffusive SNS Junctions."
 B. Verkin Institute for Low Temperature Physics and Engineering,
 National Academy of Sciences of Ukraine, Kharkov, UKRAINE; V. S.
 Shumeiko's e-mail in Sweden <a href="mailto:vitaly@fy.chalmers.se">vitaly@fy.chalmers.se;</a> preprint also
 available at <a href="http://xxx.lanl.gov/abs/cond-mat/9905233">http://xxx.lanl.gov/abs/cond-mat/9905233.</a> 74.50.+r;
 74.20.Fg; 74.80.Fp.
<p>
 Alexandre Blais and Alexandre M. Zagoskin, "Operation of Universal Gates
 in a DXD Superconducting Solid State Quantum Computer." Departement de
 Physique and Centre de Recherche en Physique du Solide, Universite de
 Sherbrooke, Sherbrooke, Quebec, CANADA J1K 2R1; e-mail
 <a href="mailto:ablais@physique.usherb.ca">ablais@physique.usherb.ca;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9905043">http://xxx.lanl.gov/abs/cond-mat/9905043.</a>
<p>
 L. N. Bulaevskii, M. J. Graf, and M. P. Maley, "The Effect of an In-
 Plane Magnetic Field on the Interlayer Transport of Quasiparticles in
 Layered Superconductors." To be published in Phys. Rev. Lett. Center
 for Materials Science, Mail Stop K765, Los Alamos National Laboratory,
 Los Alamos, NM 87545; M. J. Graf's telephone (505) 665-3035; telefax
 (505) 665-2992; e-mail <a href="mailto:graf@lanl.gov">graf@lanl.gov;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9906112">http://xxx.lanl.gov/abs/cond-mat/9906112.</a> 74.25.Fy; 74.70.Kn; 74.72.-h.
<p>
 L. N. Bulaevskii, A. E. Koshelev, V. M. Vinokur, and M. P. Maley,
 "Plasma Resonance at Low Magnetic Fields as a Probe of Vortex Line
 Meandering in Layered Superconductors." Center for Materials Science,
 Mail Stop K765, Los Alamos National Laboratory, Los Alamos, NM 87545;
 telephone (505) 667-9243; telefax (505) 665-2992.
<p>
 A. Carrington, I. Bonaldi, R. Prozorov, R. W. Giannetta, J. M. Williams,
 J. Schlueter, H. H. Wang, and U. Geiser, "Low Temperature Penetration
 Depth of kappa-(ET)2Cu[N(CN)2]Br and kappa-(ET)2Cu(NCS)2." Submitted to
 Phys. Rev. Lett. Department of Physics and Astronomy, E. C. Stoner
 Building, University of Leeds, Leeds LS2 9JT, UNITED KINGDOM; telephone
 +44 113 233-3843 or -3839; telefax +44 113 233-3846; e-mail
 <a href="mailto:a.carrington@leeds.ac.uk">a.carrington@leeds.ac.uk;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9906060">http://xxx.lanl.gov/abs/cond-mat/9906060.</a> 74.70.Kn; 74.25.Nf.
<p>
 Najib Cheggour and Damian P. Hampshire, "Unifying the Strain and
 Temperature Scaling Laws for Pinning Force Density in Superconducting
 Niobium-Tin Multifilamentary Wires." To be published in J. Appl. Phys.
 Department of Physics, Science Laboratories, University of Durham, South
 Road, Durham DH1 3LE, UNITED KINGDOM; telefax +44 191 374 3749; e-mail
 <a href="mailto:najib.cheggour@durham.ac.uk">najib.cheggour@durham.ac.uk.</a>
<p>
 Boris Chesca, "Theory of rf SQUIDs Operating at 77 K." To be published
 in Appl. Supercond. (in press). Lehrstuhl fuer Experimentalphysik VI,
 Instituet fuer Physik, Universitaet Augsburg, Universitaetsstr. 1, D-
 86135 Augsburg, GERMANY.
<p>
 P. Chowdhury and S. N. Bhatia, "Effect of Reduction in the Density of
 States on Fluctuation Conductivity in Bi2Sr2CaCu2O8+x Single Crystals."
 To be published in Physica C (in press). Contact S. N. Bhatia,
 Department of Physics, Indian Institute of Technology, Mumbai 400 076,
 INDIA; telephone +91 22 578 2545; telefax +91 22 578 3480; e-mail
 <a href="mailto:snbhatia@niharika.phy.iitb.ernet.in">snbhatia@niharika.phy.iitb.ernet.in.</a> Key words: fluctuation
 conductivity, BSCCO, superconductivity. 74.25.Fy; 74.40.+k; 74.72.Hs;
 74.72.Bk.
<p>
 A. Cigan, J. Manka, M. Mair, G. Gritzner, G. Plesch, and V. Zrubec,
 "Influence of the Tl and Hg Content on Magnetic and Transport Properties
 of the Pb,Sr-Doped Tl-1223 and Hg-1223 Superconductors." To be
 published in Physica C. Institute of Measurement Science, Slovak
 Academy of Sciences, Dubravska cesta 9, 842 19 Bratislava, SLOVAKIA;
 telephone +421 7 5941 2025; telefax +421 7 5477 5943; e-mail
 <a href="mailto:umerciga@savba.sk">umerciga@savba.sk.</a> Key words: Pb,Sr-doped Tl-1223 and Hg-1223
 superconductors, critical current density, magnetization. 74.72.Fq;
 74.72.Gr.
<p>
 A. Das, M. R. Koblischka, M. Jirsa, M. Muralidhar, S. Koishikawa, N.
 Sakai, and M. Murakami, "Correlation of Magnetic and Magneto-Optical
 Properties with Microstructure Analysis in Melt-Textured
 (Nd0.33Sm0.33Gd0.33)Ba2Cu3Oy." To be published in Physica C (in press).
 Contact M. R. Koblischka, Superconductivity Research Laboratory,
 Division 3, International Superconductivity Technology Center (ISTEC),
 1-16-25 Shibaura, Minato-ku, Tokyo 105-0023, JAPAN; telefax +81 3 3454
 9284; e-mail <a href="mailto:koblischka@istec.or.jp">koblischka@istec.or.jp.</a> Key words: magnetic and magneto-
 optical properties, (Nd0.33Sm0.33Gd0.33)Ba2Cu3Oy, melt-textured
 superconductor. 74.60.Ec; 74.60.Ge; 74.60.Jg.
<p>
 C. de Calan and F. S. Nogueira, "Scaling Critical Behavior of
 Superconductors at Zero Magnetic Field." To be published in Phys. Rev.
 B. Centre de Physique Theorique, Ecole Polytechnique, F-91128 Palaiseau
 Cedex, FRANCE; F. S. Nogueira's e-mail <a href="mailto:nogueira@cpht.polytechnique.fr">nogueira@cpht.polytechnique.fr;</a>
 preprint also available at <a href="http://xxx.lanl.gov/abs/cond-mat/9903247">http://xxx.lanl.gov/abs/cond-mat/9903247.</a>
 74.20.-z; 05.10.Cc; 11.10.-z.
<p>
 Claude de Calan and Flavio S. Nogueira, "The Superconducting Order
 Parameter and Gauge Dependence." Centre de Physique Theorique, Ecole
 Polytechnique, F-91128 Palaiseau Cedex, FRANCE; Flavio S. Nogueira's e-
 mail <a href="mailto:nogueira@cpht.polytechnique.fr">nogueira@cpht.polytechnique.fr;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9905276">http://xxx.lanl.gov/abs/cond-mat/9905276.</a> 74.20.-z; 05.10.Cc; 11.10.-z.
<p>
 Katherine D. Develos, Masanobu Kusunoki, Masashi Mukaida, and Shigetoshi
 Ohshima, "Effect of Deposition Rate on the Surface Morphology of CeO2
 Films Deposited by Pulsed Laser Deposition." To be published in Physica
 C (in press). Department of Electrical and Information Engineering,
 Yamagata University, 4-3-16 Jonan, Yonezawa 992-8510, JAPAN; telephone
 +81 238 26 3289; telefax +81 238 26 3289; e-mail <a href="mailto:d96015@eie.yz.yamagata-">d96015@eie.yz.yamagata-</a>
 u.ac.jp. Key words: CeO2 films, surface morphology, deposition rate,
 pulsed laser deposition. 68.35.Bs; 81.15.Fg.
<p>
 U. Scotti di Uccio, F. Miletto Granozio, A. di Chiara, F. Tafuri, O. I.
 Lebedev, K. Verbist, and G. van Tendeloo, "Phase Competition Between
 Y2BaCuO5 and Y2O3 Precipitates in Y-Rich YBCO Thin Films." To be
 published in Physica C. Dipartimento di Scienze Fisiche, Universita di
 Napoli "Federico II," Piazzale Tecchio 80, I-80125 Napoli, ITALY; e-mail
 <a href="mailto:scotti@axpna1.na.infn.it">scotti@axpna1.na.infn.it.</a> 74.50.+r; 74.72.Bk.
<p>
 D. Durand, B. Dalrymple, L. Eaton, J. Spargo, M. Wire, M. Dowdy, and M.
 Ressler, "10 K NbN ADC for IR Sensor Applications." To be published in
 Appl. Supercond. (in press). TRW, One Space Park, Redondo Beach, CA
 90278.
<p>
 D. K. Finnemore, K. E. Gray, M. P. Maley, D. O. Welch, D. K. Christen,
 and D. M. Kroeger, "Coated Conductor Development: An Assessment." To
 be published in Physica C (in press). Ames Laboratory-USDOE and
 Department of Physics and Astronomy, Iowa State University, Ames, Iowa
 50011; telephone (515) 294-5440; telefax (515) 294-6027; e-mail
 <a href="mailto:phys_astro@iastate.edu">phys_astro@iastate.edu.</a> Key words: ionized-beam-assisted deposition,
 rolling-assisted biaxially textured substrate, coated conductor tapes.
 74.60.Ge.
<p>
 A. V. Galaktionov, Su-Woong Lee, and Chang-Mo Ryu, "Two-Particle
 Tunneling Current in Junctions Between Anisotropic Superconductors." To
 be published in Physica C (in press). Contact Chang-Mo Ryu, Department
 of Physics, Pohang University of Science and Technology, Pohang 790-784,
 SOUTH KOREA; telephone +82 562 279 2081; telefax +82 562 279 3099; e-
 mail <a href="mailto:cmryu@postech.ac.kr">cmryu@postech.ac.kr.</a> Key words: electrical resistivity, d-wave
 superconductor, tunneling current. 74.50.+r; 74.80.Fp.
<p>
 A. Agliolo Gallitto, L. Alvarez, M. Guccione, and M. Li Vigni,
 "Microwave Second Harmonic Emission by Ba0.6K0.4BiO3: Comparison with
 YBa2Cu3O7." To be published in Physica C (in press). Contact M. Li
 Vigni, Istituto Nazionale per la Fisica della Materia and Dipartimento
 di Scienze Fisiche ed Astronomiche, Via Archirafi 36, I-90123 Palermo,
 ITALY; telephone +39 091 623 4207; telefax +39 091 616 2461; e-mail
 <a href="mailto:livigni@fisica.unipa.it">livigni@fisica.unipa.it.</a> Key words: high-temperature superconductors,
 electromagnetic field response, nonlinear effects. 74.25.Nf; 74.20.De;
 74.50.+r.
<p>
 V. Garnier, R. Caillard, A. Sotelo, and G. Desgardin, "Relationship
 Among Synthesis, Microstructure and Properties in Sinter-Forged Bi-2212
 Ceramics." To be published in Physica C (in press). Laboratoire
 CRISMAT, ISMRA, 6 Boulevard du Marechal Juin, F-14050 Caen Cedex,
 FRANCE; telephone +33 2 31 45 2915; e-mail <a href="mailto:garnier@crismat.ismra.fr">garnier@crismat.ismra.fr.</a>
 Key words: synthesis, Bi-2212, sol-gel, microstructure.
<p>
 R. Gatt, S. Christensen, B. Frazer, Y. Hirai, T. Schmauder, R. J.
 Kelley, M. Onellion, I. Vobornik, L. Perfetti, G. Margaritondo, A.
 Morawski, T. Lada, A. Paszewin, and C. Kendziora, "Superconducting Gap
 vs Wave Vector: Evidence for Hot Regions on the Fermi Surface."
 Department of Physics, B301 Sterling Hall, University of Wisconsin at
 Madison, 1150 University Avenue, Madison, WI 53706; telephone (608) 263-
 7450; telefax (608) 265-2334; e-mail <a href="mailto:rafi@src.wisc.edu">rafi@src.wisc.edu;</a> preprint also
 available at <a href="http://xxx.lanl.gov/abs/cond-mat/9906070">http://xxx.lanl.gov/abs/cond-mat/9906070.</a>
<p>
 L. Ghivelder, I. Abrego Castillo, S. Salem-Sugui, Jr., R. de Andrade,
 Jr., M. Dhalle, G. Grasso, F. Marti, and R. Flukiger, "Dimensional
 Crossover in the Irreversibility Line in (Bi,Pb)2Sr2Ca2Cu3O10." To be
 published in Supercond. Sci. & Technol. Instituto de Fisica,
 Universidade Federal do Rio de Janeiro, C.P. 68528, Rio de Janeiro, RJ
 21945-970, BRAZIL; e-mail <a href="mailto:luisghiv@if.ufrj.br">luisghiv@if.ufrj.br.</a>
<p>
 J. R. Groves, P. N. Arendt, Q. X. Jia, S. R. Foltyn, R. F. DePaula, L.
 R. Kinder, Y. Fan, and E. J. Peterson, "High Critical Current Density
 PLD YBCO Deposited on Highly Textured IBAD MgO Buffer Layers."
 Superconductivity Technology Center, Los Alamos National Laboratory, Los
 Alamos, NM 87545; telephone (505) 665-9699; telefax (505) 665-8601; e-
 mail <a href="mailto:jgroves@lanl.gov">jgroves@lanl.gov.</a>
<p>
 James R. Groves, Paul N. Arendt, Stephen R. Foltyn, Raymond F. DePaula,
 Eric J. Peterson, Terry G. Holesinger, James Y. Coulter, Robert W.
 Springer, Connie P. Wang, and Robert H. Hammond, "Ion-Beam Assisted
 Deposition of Biaxially Aligned MgO Template Films for YBCO Coated
 Conductors." Superconductivity Technology Center, Los Alamos National
 Laboratory, Los Alamos, NM 87545; telephone (505) 665-9699; telefax
 (505) 665-8601; e-mail <a href="mailto:jgroves@lanl.gov">jgroves@lanl.gov.</a>
<p>
 J. Grybos, M. Wabia, F. Kubanek, and N. Guskos, "Main- and
 Superstructure by X-ray Scattering for Annealed Single Crystal of
 YBa2Cu3O6.5." To be published in Physica C (in press). Institute of
 Physics, Technical University, al. Piastow 48, 70-311 Szczecin, POLAND;
 telephone +48 91 449 4405; telefax +48 91 4342 113; e-mail
 <a href="mailto:sunergy@arcadia.tuniv.szczecin.pl">sunergy@arcadia.tuniv.szczecin.pl.</a> Key words: superstructure of
 YBa2Cu3O0.65, Cu-O-Cu chain, Cu-Cu superconducting plane, apex-oxygen.
<p>
 Y. Hashimoto, S. Yorozu, H. Numata, M. Koike, M. Tanaka, and S. Tahara,
 "High-Speed Testing of Josephson Logic Circuits by an On-Chip Signal-
 Pattern Generator." To be published in Appl. Supercond. (in press).
 Fundamental Research Laboratories, NEC Corporation, 34 Miyukigaoka,
 Tsukuba, Ibaraki 305, JAPAN; telephone +81 298 50 2240; telefax +81 298
 56 6139; e-mail <a href="mailto:hasimoto@frl.cl.nec.co.jp">hasimoto@frl.cl.nec.co.jp.</a>
<p>
 D. G. Hinks, O. Chmaissem, Leon Ely, Carl Scott, J. D. Jorgensen, and J.
 K. Akujieze, "Reaction of YBa2Cu3O6 with Br2: Oxidation and Formation
 of Nanoscale YBa2Cu3O7." Submitted to Physica C. Materials Science
 Division-223, Argonne National Laboratory, 9700 South Cass Avenue,
 Argonne, IL 60439; telephone (630) 252-5471; e-mail <a href="mailto:hinks@anl.gov">hinks@anl.gov.</a> Key
 words: Br intercalation, O diffusion, YBa2Cu3O6Br. 74.72.Bk; 74.62.Dh;
 82.40.-g; 66.30.-h.
<p>
 Richard Hlubina, "Is the In-Plane Charge Transport in the Normal State
 of the Cuprates Anisotropic?" To be published in Physica C (in press).
 Department of Solid State Physics, Comenius University, Mlynska Dolina
 F2, 842 15 Bratislava, SLOVAKIA; telefax +421 7 654 25 882; e-mail
 <a href="mailto:hlubina@fmph.uniba.sk">hlubina@fmph.uniba.sk.</a> Key words: normal-state transport, metal-
 insulator transition, nonlinear effects. 72.15.-v; 72.20.Ht; 74.20.-z;
 74.25.Fy.
<p>
 Ling Hua, Jaimoo Yoo, Jaewoong Ko, Haidoo Kim, Hyungsik Chung, and
 Guiwen Qiao, "Fabrication of Bi-2223 Ag-Au-Mg Alloy Sheathed Tapes with
 a Controlled Melting Process." To be published in Physica C (in press).
 Superconducting Materials Research Center, General Research Institute
 for Nonferrous Metals, 2 Xin Jie Kou Wai Street, Beijing 100088,
 PEOPLE'S REPUBLIC OF CHINA; telephone +86 10 6201 4488, ext. 2210;
 telefax +86 10 6237 6971; e-mail <a href="mailto:lhua@usa.net">lhua@usa.net.</a> Key words: Bi-2223/Ag
 tapes, Ag-alloy sheath, critical current density. 74.25.Fy; 74.72.Hs;
 85.25.Kx.
<p>
 P. Huesser, H. U. Suter, E. P. Stoll, and P. F. Meier, "First-Principles
 Calculations of Hyperfine Interactions in La2CuO4." Physics Institute,
 University of Zurich, CH-8057 Zurich, SWITZERLAND; P. F. Meier's e-mail
 <a href="mailto:pfmeier@physik.unizh.ch">pfmeier@physik.unizh.ch;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9905246">http://xxx.lanl.gov/abs/cond-mat/9905246.</a>
<p>
 Shinji Inoue, Tatsunori Hashimoto, Toshihiko Nagano, and Jiro Yoshida,
 "YBaCuO/Co-Doped PrBaCuO/YBaCuO Ramp-Edge Junctions and Their
 Application to Flip-Flop Circuits." To be published in Appl. Supercond.
 (in press). Advanced Materials and Devices Laboratory, Toshiba
 Corporation, 1 Komukai Toshiba-cho, Saiwai-ku, Kawasaki 210-8582, JAPAN;
 telephone +81 44 549 2110; telefax +81 44 520 1801; e-mail shinji-
 <a href="mailto:inoue@arl.rdc.toshiba.co.jp">inoue@arl.rdc.toshiba.co.jp.</a>
<p>
 S. Ya. Istomin, J. Koehler, and A. Simon, "Crystal Structure of beta-
 ZrNCl Refined from X-ray Powder Diffraction Data, Electronic Band
 Structures of beta-ZrNCl and Superconducting LixZrNCl." To be published
 in Physica C (in press). Max-Planck-Institut fuer Festkoerperforschung,
 Heisenbergstrasse 1, D-70569 Stuttgart, GERMANY; telephone +49 711 689
 1647; telefax +49 711 689 1091; e-mail <a href="mailto:istomin@simaix.mpi-">istomin@simaix.mpi-</a>
 stuttgart.mpg.de. Key words: band structure, x-ray diffraction,
 crystal structure, synthesis, layered nitride.
<p>
 B. B. Jin, X. S. Rao, C. Y. Tan, and C. K. Ong, "A Phenomenological
 Description for Unusual Surface Impedance Behaviors of High-Tc Thin Film
 in Weak dc Magnetic Field." To be published in Physica C (in press).
 Department of Physics, National University of Singapore, BLK S12 Lower
 Kent Ridge Road, Singapore 119260, SINGAPORE; telephone +65 874 2625;
 telefax +65 777 6126; e-mail <a href="mailto:phyjinbb@nus.edu.sg">phyjinbb@nus.edu.sg.</a> Key words: unusual
 behavior of surface impedance, two-fluid model, coupled-grain model,
 high-Tc superconducting microstrip resonator. 74.25.Nf; 74.20.De;
 74.76.Bz; 74.50.+r.
<p>
 Amish G. Joshi, D. G. Kuberkar, and R. G. Kulkarni, "Influence of Hole-
 Filling by La and Hole-Doping by Ca on the Superconductivity of
 NdBa2Cu3O7-d." To be published in Physica C (in press). Contact R. G.
 Kulkarni, Department of Physics, Saurashtra University, University Road,
 Rajkot 360 005, INDIA; telephone +91 2817 8505; telefax +91 2817 7885.
 Key words: La, Ca, NdBa2Cu3O7-d.
<p>
 E. Kandyel, X.-J. Wu, S. Adachi, and S. Tajima, "High-Pressure Synthesis
 and Heat Treatments of (Hg1-xBix)Sr2Ca2Cu3Oy." To be published in
 Physica C (in press). Superconductivity Research Laboratory,
 International Superconductivity Technology Center (ISTEC), 10-13
 Shinonome 1-chome, Koto-ku, Tokyo 135-0062, JAPAN; telefax +81 3 3536
 5717; e-mail <a href="mailto:kandyel@istec.or.jp">kandyel@istec.or.jp.</a> Key words: superconductivity, high
 pressure, Hg-1223, (Hg,Bi)Sr2Ca2Cu3Oy.
<p>
 Nawazish A. Khan, Yoshiyasu Sekita, Fussiko Tateai, Takahiro Kojima,
 Katuei Ishida, Norio Terada, and Hideo Ihara, "Preparation of Biaxially
 Oriented TlCu-1234 Thin Films." To be published in Physica C (in
 press). Electrotechnical Laboratories, 1-1-4 Umezono, Tsukuba, Ibaraki
 305-8568, JAPAN; telephone +81 298 54 3379; telefax +81 298 54 5447; e-
 mail <a href="mailto:nakhan@elt.go.jp">nakhan@elt.go.jp.</a> Key words: thin films, TlCu-1234
 superconductor, low anisotropy, APE method, high Jc. 74.76.-w;
 74.76.Bz; 74.72.-h; 74.72.Jt.
<p>
 M. R. Koblischka, L. Pust, M. Jirsa, and T. H. Johansen, "Formation of
 the Low-Field Peak in Magnetization Loops of High-Tc Superconductors."
 To be published in Physica C. Superconductivity Research Laboratory,
 International Superconductivity Technology Center, 1-16-25 Shibaura,
 Minato-ku, Tokyo 105, JAPAN. 74.60.Ec; 74.60.Ge; 74.60.Jg.
<p>
 S. Kokkaliaris, S. N. Gordeev, P.A.J. de Groot, R. Gagnon, L. Taillefer,
 P. F. Henry, and M. T. Weller, "Peak Effect and Oxygen Ordering in
 YBa2Cu3O7-d Single Crystals." To be published in Physica C. Department
 of Physics and Astronomy, University of Southampton, Highfield,
 Southampton SO17 1BJ, UNITED KINGDOM; telephone +44 1703 592058;
 telefax +44 1703 593910; e-mail <a href="mailto:sk@phys.soton.ac.uk">sk@phys.soton.ac.uk.</a> Key words:
 oxygen vacancy ordering, hysteretic magnetization peak. 74.60.Ge;
 74.60.Jg; 74.72.Bk.
<p>
 A. E. Koshelev and L. N. Bulaevskii, "Fluctuation Broadening of Plasma
 Resonance Line in the Vortex Liquid State of Layered Superconductors."
 Contact Janice Coble, Materials Science Division, Argonne National
 Laboratory, 9700 South Cass Avenue, Argonne, IL 60439; telephone (630)
 252-5497; telefax (630) 252-9595; e-mail <a href="mailto:coble@anl.gov">coble@anl.gov.</a>
<p>
 A. F. Lann, M. Abu-Tair, M. Golosovsky, D. Davidov, S. Djordjevic, N.
 Bontemps, and L. F. Cohen, "A Cryogenic Microwave Scanning Near-Field
 Probe: Application to Study of High-Tc Superconductors." Submitted to
 Rev. Sci. Instrum. Racah Institute of Physics, Hebrew University of
 Jerusalem, Jerusalem 91904, ISRAEL; M. Golosovsky's telephone +972 2
 658-5139 or -6551; telefax +972 2 5617 805; e-mail <a href="mailto:golos@vms.huji.ac.il">golos@vms.huji.ac.il.</a>
 07.57.-c; 07.79.-v; 74.25.Nf.
<p>
 A. F. Lann, M. Abu-Tair, M. Golosovsky, D. Davidov, A. Goldgirsch, and
 V. Beilin, "Magnetic Field-Modulated Microwave Reflectivity of High-Tc
 Superconductors Studied by the Near-Field mm-Wave Microscopy."
 Submitted to Appl. Phys. Lett. Racah Institute of Physics, Hebrew
 University of Jerusalem, Jerusalem 91904, ISRAEL; M. Golosovsky's
 telephone +972 2 658-5139 or -6551; telefax +972 2 5617 805; e-mail
 <a href="mailto:golos@vms.huji.ac.il">golos@vms.huji.ac.il.</a> 07.57.-c; 07.79.-v; 74.25.Nf.
<p>
 A. F. Lann, M. Golosovsky, and D. Davidov, "Microwave Near-Field
 Polarimetry." Submitted to Appl. Phys. Lett. Racah Institute of
 Physics, Hebrew University of Jerusalem, Jerusalem 91904, ISRAEL; M.
 Golosovsky's telephone +972 2 658-5139 or -6551; telefax +972 2 5617
 805; e-mail <a href="mailto:golos@vms.huji.ac.il">golos@vms.huji.ac.il.</a>
<p>
 Sang Young Lee, J. H. Suh, O. K. Kwon, J. Y. Cho, B. H. Park, J. H. Lee,
 V. A. Komashko, Y. H. Kim, T. S. Hahn, B. Oh, H. T. Kim, and Hu-Jong
 Lee, "Microwave Properties and Applications of Y-Ba-Cu-O Thin Films
 Grown on Various Substrates." To be published in Appl. Supercond. (in
 press). Department of Physics and Center for Advanced Materials and
 Devices, Konkuk University, Seoul 143-701, SOUTH KOREA.
<p>
 H. Q. Li, R. H. Ono, D. A. Rudman, L. R. Vale, and S. H. Liou,
 "Multilayer Processing of High-Tc Films and Stacked Bicrystal Josephson
 Junctions." To be published in Appl. Supercond. (in press). National
 Institute of Standards and Technology, Boulder, CO 80303.
<p>
 N. I. Lundin, L. Y. Gorelik, R. I. Shekhter, V. S. Shumeiko, and M.
 Jonson, "Microwave Controlled Phase Coherent Transport in Mesoscopic S-
 N-S Structures." Department of Applied Physics, Chalmers University of
 Technology and Goteborg University, S-41296 Goteborg, SWEDEN; e-mail
 <a href="mailto:nlundin@fy.chalmers.se">nlundin@fy.chalmers.se;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9905386">http://xxx.lanl.gov/abs/cond-mat/9905386.</a>
<p>
 Kazushige Machida, Tsutomu Nishira, and Tetsuo Ohmi, "Orbital Symmetry
 of a Triplet Pairing in a Heavy Fermion Superconductor UPt3."
 Department of Physics, Okayama University, Okayama 700-8530, JAPAN; e-
 mail <a href="mailto:machida@mp.okayama-u.ac.jp">machida@mp.okayama-u.ac.jp;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9906105">http://xxx.lanl.gov/abs/cond-mat/9906105.</a> Key words: heavy fermion
 superconductor, UPt3, triplet pairing, orbital symmetry, thermal
 conductivity, ultrasound attenuation, bipolar state, planar state.
<p>
 Y. M. Malozovsky and J. D. Fan, "Magnetic Flux Quantization in
 Superconductors and the Aharonov-Bohm Effect." Department of Physics,
 Southern University and A & M College, Baton Rouge, LA 70813. 74.20.De;
 74.25.-q.
<p>
 T. A. Mamedov and M. de Llano, "Boson-Exchange Superconductor Model with
 a Van Hove Singularity." To be published in Phys. Lett. A (in press).
 Department of Physics Engineering, Hacettepe University, Beytepe 06532,
 Ankara, TURKEY; e-mail <a href="mailto:tevfik@eti.cc.hun.edu.tr">tevfik@eti.cc.hun.edu.tr.</a>
<p>
 Cesar A. Mancini, Nada Vukovic, Mark F. Bocko, Marc J. Feldman, and
 Andrea M. Herr, "Experimental Investigation of RSFQ Circular Shift
 Registers." To be published in Appl. Supercond. (in press). Department
 of Electrical Engineering, Superconducting Digital Electronics,
 University of Rochester, Rochester, NY 14627; telephone (716) 275-8135;
 telefax (716) 473-0486; e-mail <a href="mailto:mancini@ece.rochester.edu">mancini@ece.rochester.edu.</a>
<p>
 I. Matsubara, M. Paranthaman, A. Singhal, C. Vallet, D. F. Lee, P. M.
 Martin, R. D. Hunt, R. Feenstra, Chau-Yun Yang, and S. E. Babcock,
 "Preparation of Textured YBCO films Using All-Iodide Precursors." To be
 published in Physica C (in press). Osaka National Research Institute,
 1-8-31 Midorigaoka, Ikeda, Osaka 563, JAPAN. Key words: Y123 films,
 metal iodides, solution process, textured films. 74.72.Bk; 74.76.Bz.
<p>
 V. Meerovich, V. Sokolovsky, S. Goren, and G. Jung, "ac Losses in High-
 Temperature Superconductor BSCCO Hollow Cylinders with Induced Current."
 To be published in Physica C (in press). Department of Physics, Ben-
 Gurion University of the Negev, P.O. Box 653, 84105 Beer-Sheva, ISRAEL;
 telephone +972 7 647 2458; telefax +972 7 647 2903. Key words: ac
 losses, high-Tc superconductors, critical state.
<p>
 O. V. Misochko, K. Kisoda, H. Harima, K. Mizoguchi, K. Sakai, and S.
 Nakashima, "Mixing of Low-Frequency Raman-Active Phonons Studied by
 Femtosecond Pump-Probe Spectroscopy." To be published in Physica C.
 Communications Research Laboratory, Kansai Advanced Research Center,
 588-2 Iwaoka, Kobe-shi, Hyogo 651-2401, JAPAN; telephone +81 78 969
 2197; telefax +81 78 969 2154; e-mail <a href="mailto:misochko@crl.go.jp">misochko@crl.go.jp.</a> Key words:
 femtosecond time-resolved spectroscopy, lattice dynamics, high-Tc
 superconductors. 74.25.Kc; 74.25.Gz; 74.72.Bk; 74.76.-w.
<p>
 A. Mourachkine, "Evidence for the Presence of the Magnetically Mediated
 Superconductivity in Hole-Doped Cuprates." Service de Physique des
 Solides, Universite Libre de Bruxelles, CP233, Boulevard du Triomphe, B-
 1050 Brussels, BELGIUM; telephone +32 2 650 5751; telefax +32 2 650
 5916; e-mail <a href="mailto:anmourac@ulb.ac.be">anmourac@ulb.ac.be;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9905308">http://xxx.lanl.gov/abs/cond-mat/9905308.</a>
<p>
 M. Muralidhar, M. R. Koblischka, and M. Murakami, "Submicron Size
 Gd2BaCuO5 Particles as Source for Large Critical Current Densities in
 (Nd0.33Eu0.33Gd0.33)Ba2Cu3Oy." To be published in European Physical J.
 Appl. Phys. Superconductivity Research Laboratory, International
 Superconductivity Technology Center (ISTEC), 3-35-2 Iioka-Shinden,
 Morioka, Iwate 020-0852, JAPAN; telephone +81 19 635-9015 or -9016;
 telefax +81 19 635-9017; e-mail <a href="mailto:miryala@istec.or.jp">miryala@istec.or.jp.</a>
<p>
 Miryala Muralidhar and Masato Murakami, "Jc-B Properties of Melt-
 Processed (Nd,Eu,Gd)-Ba-Cu-O with Gd2BaCuO5 Second Phase." To be
 published in Advances in Supercond. XI: Proc. of the 11th Int. Symp. on
 Superconductivity (ISS'98), Fukuoka, Japan, Nov. 16-19, 1998; edited by
 N. Koshizuka and S. Tajima (Springer-Verlag, Tokyo). Superconductivity
 Research Laboratory, International Superconductivity Technology Center
 (ISTEC), 3-35-2 Iioka-Shinden, Morioka, Iwate 020-0852, JAPAN; telephone
 +81 19 635-9015 or -9016; telefax +81 19 635-9017; e-mail
 <a href="mailto:miryala@istec.or.jp">miryala@istec.or.jp.</a> Key words: melt processing, NEG123, Gd211, Pt
 addition, critical current density.
<p>
 M. Napoletano, J. M. Gallardo Amores, E. Magnone, G. Busca, and M.
 Ferretti, "Skeletal Infrared Spectra and Structural Properties of La2-
 xSrxCuO4 and La2-xBaxCuO4 Cuprate Powders in the 0 <= x <= 0.125
 Region." To be published in Physica C (in press). INFM and
 Dipartimento di Chimica e Chimica Industriale, Universita di Genova, Via
 Dodecaneso 31, I-16146 Genova, ITALY; telephone +39 010 353 6102;
 telefax +39 010 362 8252; e-mail <a href="mailto:htsclab@chimica.unige.it">htsclab@chimica.unige.it.</a> Key words:
 infrared spectroscopy, structure (of), substitution effect, synthesis
 (of).
<p>
 T. Ogawa, "Effect of the Cooling Time in YBa2Cu3O7-d Film Process on the
 Electrical Properties of Grain Boundary Josephson Junctions on SrTiO3
 (100) Bicrystal with the Misorientation Angle of 36.8 degrees." To be
 published in Physica C (in press). Semiconductor Device Research
 Center, Matsushita Electronic, 1-1 Saiwai-chou, Takatsuki, Osaka 569-
 1143, JAPAN; telephone +81 11 706 7176; telefax +81 11 716 6004; e-mail
 <a href="mailto:ogawa@eng.hokudai.ac.jp">ogawa@eng.hokudai.ac.jp</a> or <a href="mailto:ogawa@erl.mec.mei.co.jp">ogawa@erl.mec.mei.co.jp.</a> Key words: cooling
 time, pulsed laser deposition, YBa2Cu3O7-d, bicrystal, Josephson
 junctions, a spread of the device parameters.
<p>
 Akihiro Oka, Satoshi Koyama, Teruo Izumi, and Yuh Shiohara, "X-ray
 Absorption Study of Oxygen Configurations in YBa2Cu3O7-d Single Crystals
 Annealed by Two Step Heat Treatments." To be published in Physica C (in
 press). Superconductivity Research Laboratory, Division 4,
 International Superconductivity Technology Center (ISTEC), 10-13
 Shinonome 1-chome, Koto-ku, Tokyo 135-0062, JAPAN; telephone +81 3 3536
 5711; telefax +81 3 3536 5705; e-mail <a href="mailto:okaaki@istec.or.jp">okaaki@istec.or.jp.</a> Key words:
 YBa2Cu3O7-d, EXAFS, oxygen configuration, Jc-H curve, peak effect.
<p>
 J. P. Pekola, J. J. Toppari, M. Aunola, M. T. Savolainen, and D. V.
 Averin, "Adiabatic Transport of Cooper Pairs in Arrays of Josephson
 Junctions." Submitted to Phys. Rev. Lett. Department of Physics,
 University of Jyvaskyla, P.O. Box 35, FIN-40351 Jyvaskyla, FINLAND; J.
 J. Toppari's e-mail <a href="mailto:jajuto@phys.jyu.fi">jajuto@phys.jyu.fi;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9904264">http://xxx.lanl.gov/abs/cond-mat/9904264.</a> 73.23.Hk; 74.50.+r.
<p>
 J. J. Rodriguez-Nunez and A. A. Schmidt, "Comment on 'Superconducting
 Phases in the Presence of Coulomb Interaction: From Weak to Strong
 Correlations.'" Submitted to Phys. Rev. B. Departamento de Fisica-
 CCNE, Universidade Federal de Santa Maria, 97105-900 Santa Maria RS,
 BRAZIL; e-mail <a href="mailto:jjrn@ccne.ufsm.br">jjrn@ccne.ufsm.br.</a> 74.20.Fg; 74.60.-w; 74.72.-h.
<p>
 David J. Rogers, Philippe Bove, and Ferechteh Hosseini Teherani,
 "Critical Parameters in the Molecular Beam Epitaxy Growth of Bi2Sr2Can-
 1CunOy and (Sr,Ca)mCunOy Superconductor Thin Films." To be published in
 Supercond. Sci. & Technol. Wintici R & D Centre, 17 Rue Jean Moulin, F-
 94300 Vincennes, FRANCE; e-mail <a href="mailto:drogers610@aol.com">drogers610@aol.com.</a>
<p>
 A. H. Romero, David W. Brown, and Katja Lindenberg, "Electron-Phonon
 Correlations, Polaron Size, and the Nature of the Self-Trapping
 Transition." Max-Planck-Institut fuer Festkoerperforschung,
 Heisenbergstrasse 1, D-70569 Stuttgart, GERMANY; Katja Lindenberg's e-
 mail at University of California, San Diego <a href="mailto:kl@hypatia.ucsd.edu">kl@hypatia.ucsd.edu;</a>
 preprint also available at <a href="http://xxx.lanl.gov/abs/cond-mat/9905174">http://xxx.lanl.gov/abs/cond-mat/9905174.</a>
 71.38.+i; 71.15.-m; 71.35.Aa; 72.90.+y.
<p>
 L. F. Rybaltchenko, A.G.M. Jansen, P. Wyder, L. V. Tjutrina, P. C.
 Canfield, C. V. Tomy, and D.McK. Paul, "Point-Contact Study of the
 Magnetic Superconductor HoNi2B2C." To be published in Physica C (in
 press). Contact A.G.M. Jansen, Grenoble High Magnetic Field Laboratory,
 Max-Planck-Institut fuer Festkoerperforschung and Centre National de la
 Recherche Scientifique, B.P. 166, F-38042 Grenoble Cedex 9, FRANCE;
 telephone +33 4 7688 1058; telefax +33 4 7685 5610; e-mail
 <a href="mailto:ljansen@labs.polycnrs-gr.fr">ljansen@labs.polycnrs-gr.fr.</a> Key words: magnetic superconductors,
 borocarbides, point contacts, order parameter. 74.70.Ad; 74.80.Fp.
<p>
 P. D. Sacramento, "Hall Conductance of a Pinned Vortex Lattice in a High
 Magnetic Field." To be published in J. Phys.: Cond. Matter.
 Departamento de Fisica and CFIF, Instituto Superior Tecnico, Av. Rovisco
 Pais, 1096 Lisboa Codex, PORTUGAL; e-mail <a href="mailto:pdss@fidelio.ist.utl.pt">pdss@fidelio.ist.utl.pt;</a>
 preprint also available at <a href="http://xxx.lanl.gov/abs/cond-mat/9905181">http://xxx.lanl.gov/abs/cond-mat/9905181.</a>
<p>
 S. Salem-Sugui, Jr., L. Ghivelder, M. Friesen, K. Moloni, B. Veal, and
 P. Paulikas, "Temperature Dependence of the Second Magnetization Peak in
 Deoxygenated YBa2Cu3O6.65 Single Crystal." Instituto de Fisica,
 Universidade Federal do Rio de Janeiro, C.P. 68528, Rio de Janeiro, RJ
 21945-970, BRAZIL; e-mail <a href="mailto:said@if.ufrj.br">said@if.ufrj.br.</a>
<p>
 M. Salvato, C. Attanasio, G. Carbone, T. Di Luccio, S. L. Prischepa, R.
 Russo, and L. Maritato, "Bi2Sr2CuO6+d/ACuO2 (A=Ca,Sr) Superconducting
 Multilayers Obtained by Molecular Beam Epitaxy." To be published in
 Physica C (in press). Dipartimento di Fisica and INFM, Universita degli
 Studi di Salerno, I-84081 Baronissi (Salerno), ITALY. Key words:
 superconducting multilayers, molecular beam epitaxy, reflection high
 energy electron diffraction.
<p>
 P. V. Shevchenko, A. W. Sandvik, and O. P. Sushkov, "Double-Layer
 Heisenberg Antiferromagnet at Finite Temperature: Brueckner Theory and
 Quantum Monte Carlo Simulations." School of Physics, University of New
 South Wales, Sydney 2052, AUSTRALIA; telefax +61 2 9385 6060; e-mail
 <a href="mailto:pavel@newt.phys.unsw.edu.au">pavel@newt.phys.unsw.edu.au;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9905227">http://xxx.lanl.gov/abs/cond-mat/9905227.</a> 75.10.Jm; 75.30.Kz; 75.50.Ee.
<p>
 M. E. Simon and C. M. Varma, "Magnetic Impurities in d-Wave
 Superconductors." Bell Laboratories, Lucent Technologies, Murray Hill,
 NJ 07974; e-mail <a href="mailto:mesimon@lucent.com">mesimon@lucent.com;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9905349">http://xxx.lanl.gov/abs/cond-mat/9905349.</a>
<p>
 P. M. Singer, A. W. Hunt, and T. Imai, "Systematic [63]^Cu NQR Studies
 of the Stripe Phase in La1.6-xNd0.4SrxCuO4 for 0.07 <= x <= 0.25."
 Department of Physics and Center for Materials Science and Engineering,
 Massachusetts Institute of Technology, Cambridge, MA 02139; A. W. Hunt's
 e-mail <a href="mailto:awhunt@mit.edu">awhunt@mit.edu;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9906140">http://xxx.lanl.gov/abs/cond-mat/9906140.</a> 74.25.Nf; 74.72.Dn.
<p>
 M. V. Subbarao, H. Rajagopal, A. Sequeira, and R. G. Kulkarni,
 "Structural Studies of the Superconducting La3.5-x-yYyCa2xBa3.5-xCu7Oz
 System." To be published in Physica C (in press). Contact R. G.
 Kulkarni, Department of Physics, Saurashtra University, Rajkot 360 005,
 INDIA; telephone +91 2817 8505; telefax +91 2817 7885. Key words:
 La3.5-x-yYyCa2xBa3.5-xCu7Oz system, Rietveld refinement, Ca and Y ions.
<p>
 Mitsuaki Takigawa, Masanori Ichioka, and Kazushige Machida, "Theory of
 Vortex Excitation Imaging via an NMR Relaxation Measurement."
 Department of Physics, Okayama University, Okayama 700-8530, JAPAN; e-
 mail <a href="mailto:takigawa@mp.okayama-u.ac.jp">takigawa@mp.okayama-u.ac.jp;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9906087">http://xxx.lanl.gov/abs/cond-mat/9906087.</a> 74.60.Ec; 74.25.Jb; 76.60.Pc.
<p>
 K. R. Thurber, T. Imai, T. Saitoh, M. Azuma, M. Takano, and F. C. Chou,
 "[63]^Cu NQR Evidence of Dimensional Crossover to Anisotropic 2D Regime
 in S = 1/2 Three-Leg Ladder Sr2Cu3O5." Department of Physics and Center
 for Materials Science and Engineering, Massachusetts Institute of
 Technology, Cambridge, MA 02139; e-mail <a href="mailto:kentt@mit.edu">kentt@mit.edu;</a> preprint also
 available at <a href="http://xxx.lanl.gov/abs/cond-mat/9906141">http://xxx.lanl.gov/abs/cond-mat/9906141.</a>
<p>
 C. J. van der Beek, M. Konczykowski, R. J. Drost, P. H. Kes, N.
 Chikumoto, and S. Bouffard, "Entropy, Vortex Interactions and the Phase
 Diagram of Heavy-Ion Irradiated Bi2Sr2CaCu2O8+d." Laboratoire des
 Solides Irradies, Ecole Polytechnique, F-91128 Palaiseau, FRANCE; e-mail
 <a href="mailto:beek@hp1sesi.polytechnique.fr">beek@hp1sesi.polytechnique.fr;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9906096">http://xxx.lanl.gov/abs/cond-mat/9906096.</a> 74.60.Ec; 74.60.Ge.
<p>
 M. v. Zimmermann, T. Frello, N. H. Andersen, J. Madsen, M. Kaell, O.
 Schmidt, T. Niemoeller, J. R. Schneider, H. F. Poulsen, Th. Wolf, R.
 Liang, P. Dosanjh, and W. N. Hardy, "Oxygen Ordering Superstructures and
 Structural Phase Diagram of YBa2Cu3O6+x Studied by Hard X-ray
 Diffraction." Submitted to Phys Rev. B. Department of Physics,
 Brookhaven National Laboratory, Upton, NY 11973; e-mail
 <a href="mailto:vmartin@solids.phy.bnl.gov">vmartin@solids.phy.bnl.gov;</a> preprint also available at
 <a href="http://xxx.lanl.gov/abs/cond-mat/9906251">http://xxx.lanl.gov/abs/cond-mat/9906251.</a>
<p>
 Nada Vukovic and Marc J. Feldman, "Single Flux Quantum One-Decimal-Digit
 RNS Adder." To be published in Appl. Supercond. (in press). University
 of Rochester, Rochester, NY 14627.
<p>
 Z. H. Wang and H. Zhang, "Effective Activation Energy U_[e](T,J,H) in
 Textured Bi1.84Pb0.4Sr2Ca2Cu3Oy Silver Clamped Thick Films." To be
 published in Physica C. Shanghai Institute of Metallurgy, Chinese
 Academy of Sciences, Shanghai 200050, PEOPLE'S REPUBLIC OF CHINA;
 telephone +86 21 6251 1070, ext. 8924; telefax +86 21 6251 3510; e-mail
 <a href="mailto:zhwang@itsvr.sim.ac.cn">zhwang@itsvr.sim.ac.cn.</a> 74.60.Ge; 74.72.Bk; 74.76.-w.
<p>
 Matthias Weiss and Robert Schoellhorn, "Cathodic Reduction of
 Superconducting Oxocuprates YBa2Cu3O7-x at High Current Densities." To
 be published in J. Solid State Electrochem. Contact Robert Schoellhorn,
 Institut fuer Anorganische und Analytische Chemie, Technische
 Universitaet Berlin, Strasse des 17. Juni 135, D-10623 Berlin, GERMANY.
 Key words: electron-proton transfer, topotactic processes, oxocuprates,
 high ionic strength electrolytes.
<p>
 Lian-Ao Wu, Mike Guidry, Yang Sun, and Cheng-Li Wu, "The SO(5) Theory as
 a Critical Dynamical Symmetry." Submitted to Phys. Rev. Lett.
 Department of Physics, Jilin University, Changchun, Jilin 130023,
 PEOPLE'S REPUBLIC OF CHINA; Yang Sun's e-mail at University of
 Tennessee, Knoxville <a href="mailto:yangsun@utknp3.phys.utk.edu">yangsun@utknp3.phys.utk.edu;</a> preprint also
 available at <a href="http://xxx.lanl.gov/abs/cond-mat/9905436">http://xxx.lanl.gov/abs/cond-mat/9905436.</a>
<p>
 W. M. Yang, Y. Feng, L. Zhou, P. X. Zhang, M. Z. Wu, Shaokai Chen, X. Z.
 Wu, and W. Gawalek, "The Effect of the Grain Alignment on the Levitation
 Force in Single Domain YBa2Cu3Oy Bulk Superconductors." To be published
 in Physica C (in press). Superconducting Material Research Center,
 Northwest Institute for Nonferrous Metal Research, P.O. Box 51, Xi'an,
 Shaanxi 710016, PEOPLE'S REPUBLIC OF CHINA; telephone +86 29 623
 1079; telefax +86 29 623 1103; e-mail <a href="mailto:pxzhang@mail.xanet.edu.cn">pxzhang@mail.xanet.edu.cn.</a>
 Key words: YBCO superconductors, single domain, melt growth,
 anisotropy properties, levitation force.
<p>
 Jaeun Yoo and Dojun Youm, "Fabrication of YBCO Coated Conductors Using
 Biaxially Textured Pt0.66Pd0.34 Tapes as Their Substrates." To be
 published in Physica C (in press). Contact Dojun Youm, Department of
 Physics, Korea Advanced Institute of Science and Technology, Kusong-
 Dong, Yusung-Gu, Taejon 305-701, SOUTH KOREA; telephone +82 42 869
 2570; telefax +82 42 869 2510; e-mail <a href="mailto:djyoum@sorak.kaist.ac.kr">djyoum@sorak.kaist.ac.kr.</a>
 Key words: high Tc, superconducting, YBCO, coated conductor,
 nonmagnetic, Pt-Pd tape.
<p>
 <hr>
<p>
 COMING EVENTS
 (An * indicates a previously listed event. Also see complete listing of
 upcoming conferences and workshops at our Web site
 <a href="http://www.iitap.iastate.edu/htcu/comevents.html.)">http://www.iitap.iastate.edu/htcu/comevents.html.)</a>
<p>
 *Sept. 19 - 23, 1999: Superconducting Materials Aspects: Research &
 Technology (SMART 99), Giens Peninsula, Hyeres, France. Second SMART
 Conference; satellite to the EUCAS'99 Conference in Sitges, Barcelona,
 Spain (Sept. 14-17, 1999). Will provide an opportunity to present new
 results and exchange ideas on the following research and technology
 topics: phase chemistry and processing of bulk and thick-film
 materials, crystal-growth processes, relationships between materials
 structure and relevant properties, electromagnetic interactions, and
 applications. Materials of interest are mainly superconducting
 ceramics, superionic conductors, giant-magnetoresistive materials,
 nanocrystals, ferroelectrics, organic electronics and photonics
 materials, nanotubes, thermoelectric materials, and ceramic matrix
 composites. Organizers plan for four working days without parallel
 sessions. Program will consist of keynote and contributed papers (oral
 or posters). Industrial participants are encouraged to present
 technological state-of-the-art and to raise practical questions. Level
 of the meeting is that of an advanced research workshop with ample time
 for discussions. For information, contact Gilbert Vacquier, Co-Chair
 and Conference Secretary, LPCM (Case 26), Centre Saint-Charles, 3 Place
 V. Hugo, F-13331 Marseille Cedex 03, France; telephone +33 491 10-6271;
 telefax +33 491 10-6448 or -6237; e-mail <a href="mailto:smart@newsup.univ-mrs.fr">smart@newsup.univ-mrs.fr;</a> Web
 site <a href="http://www.supras.phys.ulg.ac.be/smart-99.html">http://www.supras.phys.ulg.ac.be/smart-99.html.</a>
<p>
 <hr>
<p>
 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.
<p>
 The information contained herein is intended for limited distribution.
 Readers are expected to respect the rights of the authors.
<p>
 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: <a href="mailto:MITRA@AMESLAB.GOV">MITRA@AMESLAB.GOV</a>
 or <a href="mailto:MITRA@IASTATE.EDU">MITRA@IASTATE.EDU</a>
<p>
<p>
 Project Director/Editor: Sreeparna Mitra
 Science Editor: John R. Clem
 High-Tc Update, Vol. 13, #14, July 15, 1999.
 <hr>