HIGH-Tc UPDATE E-MAIL VERSION, VOL. 10, NO. 15, Aug. 1, 1996.
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,
NIST, and other agencies, organizations, and individuals.
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explanatory marks as needed to the text file. For example, a
carat
(10^5) indicates a superscript (ten to the fifth). A carat followed
by
a bracket (cm^[-2]) indicates everything within the brackets is
superscripted (centimeter to the minus 2). A bracket followed by
a
carat ([18]^O) indicates everything before the carat is
superscripted.
An underline (M_i) indicates a subscript (M subscript i). Most
Greek
letters are spelled out (Delta, mu, tau, pi, Omega), although delta
is
left as "d." In most instances, easily recognizable formulas or
units
are left as they appear: Tc, Jc, YBa2Cu3O7, O2. Mu-m is changed
to
micrometers. Diacritical marks (accents, tildes, carats, etc.)
are
removed, but the German umlaut (e.g., a, o, or u with two dots over
it)
is changed into a, o, or u followed by e. If needed for clarity,
hyphens are occasionally inserted between spelled-out Greek letters
or
symbols (ohm-cm, sin-theta).
NOTA BENE:
Vortices
Features in resistivity and magnetization measurements on crystals
of
YBa2Cu3O7-d (YBCO) and Bi2Sr2CaCu2O8+d (Bi-2212) previously have
been
interpreted as evidence for a vortex-lattice melting line H_m(T) in
the
H-T (magnetic field-temperature) plane, with a vortex solid at
low
fields and temperatures, and a vortex liquid at high fields and
temperatures. Theoretical work has suggested that in clean
materials
this melting transition is first-order, with an accompanying
latent
heat. A paper by A. Schilling (LBNL and UC-Berkeley) et al., soon
to
appear in Nature, now reports that such a latent heat has been
observed
in highly sensitive calorimetric measurements performed on an
untwinned
single crystal of YBCO. The value obtained, L ~~ 0.45 k_BT per
pancake
vortex over the temperature range 80-89 K, is consistent with
that
inferred from magnetization data using the Clapeyron equation.
These
results provide compelling experimental evidence for a
first-order
vortex-lattice melting transition at a well-defined phase
boundary
H_m(T).
Small-angle-neutron-scattering (SANS) measurements at 6.4 K by U.
Yaron
(Bell Labs) et al. of the vortex-lattice structure in a high-quality
Nb
crystal (Tc = 9.16 K) have been carried out in magnetic fields H
from
0.7 H_[c2] to the upper critical field H_[c2], over the range where
the
peak effect is seen in the transport critical current density Jc.
The
authors' SANS, transport, and thermodynamic studies indicate that as
the
field increases, the vortex structure evolves from a lattice to a
hexatic vortex glass to a vortex glass, with all phases exhibiting
a
finite critical current. The authors emphasize that the peak effect
in
Nb is associated with static disordering and not a vortex-lattice
melting transition.
Using Langevin dynamics, S. Ryu (Ohio State) et al. have
investigated
the dynamics of vortices in a model disordered two-dimensional
superconductor subjected to a uniform driving current. The
simulations
provide numerical evidence for a dynamical phase transition between
a
plastic-flow regime and a moving hexatic glass. The simulated
current-
voltage characteristics are in excellent agreement with recent
transport
measurements on amorphous Mo77Ge23 thin-film superconductors.
As shown in a recent paper by G. Blatter (ETH-Zurich) et al. [Phys.
Rev.
Lett. 77, 566 (1996)], in a type-II superconductor the gap variation
in
a vortex core induces a local charge modulation. The authors
calculate
the electric field distribution in the half space above a field-
penetrated superconductor. The resulting field is that of an
atomic-
size dipole with dipole moment of the order of ea_B, where a_B is
the
Bohr radius.
Flux Imaging
An efficient inversion scheme has been developed by R. J. Wijngaarden
et
al. (Amsterdam) to obtain the local currents J(x,y) in a
superconductor
from measurements of the z component of the magnetic field
H_z(x,y)
measured in a plane above its surface using magneto-optical
indicators.
The new method works for samples of arbitrary thickness provided
that
the current vector has only x and y components. Data storage is
much
lower and convergence much faster than in previously reported
schemes.
The authors also report studies of the influence of the sample
aspect
ratio and the distance of observation upon the measured field H_z.
The
current calculated from the magneto-optical observation of a
Bi2Sr2CaCu2O8+d (Bi-2212) single crystal was found to be in good
agreement with the values measured directly using a torque
magnetometer.
In a second preprint by Wijngaarden (Amsterdam) et al., the
authors
apply the above method to examine the effect of twin planes on
the
superconducting current flow in a YBa2Cu3O7-d single crystal
containing
only two twin boundaries. The authors found that magnetic flux
enters
the crystal very easily along the twin boundaries, but that it does
not
leave the sample preferentially along these boundaries.
According to Ch. Jooss et al. (MPI-Stuttgart), all epitaxial
YBa2Cu3O7-d
thin films show surface roughness arising from island growth. To
investigate surface pinning, the authors carried out combined
magneto-
optical and atomic-force-microscopy (AFM) studies.
Magneto-optical
measurements of the spatial distribution of magnetic flux density on
the
surface of thin YBCO films allows an accurate determination of
the
critical current density Jc. The authors concluded that surface
pinning
causes between 10% and 30% of the critical current densities of
epitaxial YBCO thin films.
RBa2Cu3O7-d
Solid solutions of superconducting (NdyY1-y)Ba2Cu3O7-d and
(SmyY1-
y)Ba2Cu3O7-d have been synthesized and studied by P. Schaetzle et
al.
(Dresden). The authors found that (NdyY1-y)Ba2Cu3O7-d composite
samples
melt-textured in air show 77 K critical current densities of about
4.5 x
10^4 A/cm^2, higher than those of corresponding YBa2Cu3O7-d
samples.
The authors also observed a double exchange of both Y^[3+] and
Ba^[2+]
by Nd^[3+] [or by Sm^[3+] in (SmyY1-y)Ba2Cu3O7-d] in these
materials.
The results indicate that vacancies on Ba sites exist as defects in
the
substituted 123 phase. Microstructural studies revealed the presence
of
(Nd/Y)-211 or (Sm/Y)-211 inclusions. The authors anticipate that
optimization of the processing conditions will further enhance
the
samples' properties.
Melt-textured Nd1-yBa2+yCu3O7-d samples with Tc = 94 K and
Jc(B=0,T=77K)
= 4.6 x 10^4 A/cm^2 have been prepared by W. Bieger (Dresden) et
al.
using an isothermal route. However, the authors did not find a peak
in
Jc(B,T) in the field range 1-3 T, as observed previously. The
authors
suggest that such a peak arises from defects in the O sublattice.
Using the copper nuclear quadrupole resonance (NQR) spectra of
RBa2Cu3O6+x (R-123; R = Y, Nd, La; 0 <= x <= 1), H.
Luetgemeier
(Juelich) et al. have determined the relative intensities of the
resonance lines belonging to the Cu(1) (CuO-chain) sites with
two,
three, and four nearest-neighbor O atoms as a function of the
oxygen
concentration x. The different intensity distributions for different
R
atoms shows that, unlike the behavior in Y-123 for which the oxygen
ions
in the basal plane order preferentially into long chain fragments
leading to the ortho-II structure at 0.5 < x < 0.6, the
ordering in Nd-
123 can be described by a model in which the chain fragments are
formed
by random occupation of the O sites along the fragment direction.
The microstructure and superconducting properties of melt-processed
YBCO
prepared by several routes [melt-powder-melt-growth (MPMG),
powder-melt-
processing (PMP), and solid-liquid-melt-growth (SLMG)] have been
comparatively investigated by I. Monot et al. (Caen). The authors
found
that the highest critical current densities between 0 T and 1 T
were
obtained for the MPMG samples.
A systematic study of the temperature dependence of the in-plane
thermal
conductivity K(T) in oxygen-deficient single crystals of YBa2Cu3O6+x
(0
< x < 1) has been carried out by A. V. Inyushkin (Kurchatov
Institute)
et al. Below 200 K, the authors found an anomalous dependence of
K(T)
in insulating YBa2Cu3O6, which they take to be evidence for an
unknown
phonon relaxation process. For underdoped superconducting crystals,
the
authors found that features in the metallic normal-state K(T)
correlate
with spin-gap behavior of the spin and charge excitation spectrum.
The
authors interpret these features of K(T) in terms of a
spin-phonon
interaction.
Using a newly developed vibrating sample magnetometer (VSM)
combined
with a hybrid magnet, G. C. Han (Tohoku) et al. have measured the
magnetic hysteresis of quench-melt-growth (QMG) processed YBCO over
a
wide temperature and field range (4.2 K <= T < 91 K and 0 <=
H <= 23 T).
A fishtail effect [second peak in M(H), corresponding to a maximum in
Jc
at 5-7 T] appeared at intermediate temperatures (40 K < T < 70
K). The
authors studied the shape of the magnetization hysteresis curves
at
different sweep rates and found that there was no suppression of
the
fishtail effect even for a sweep rate of 30 T/min.
A magnetization study of the fishtail effect in Ba0.6K0.4BiO3
single
crystals has been carried out by W. Harneit (Grenoble) et al.
using
three techniques with different time scales down to 10^[-4] s.
The
fishtail effect was observed over a large temperature range down to
the
shortest time scale. The authors conclude that the fishtail effect
in
Ba0.6K0.4BiO3 and probably in other high-Tc superconductors is an
intrinsic feature of Jc(B) and is not due to flux creep.
Bi Cuprates
The magnetic properties of Bi2Sr2Ca1-xYxCu2O8+d single crystals
with
different Y content have been studied by G. Villard et al. (Caen).
At
optimum doping, the onset Tc reaches 91.5 K and the irreversibility
line
is raised. In addition, the fishtail feature disappears, indicating
a
considerably enhanced pinning efficiency in the optimally doped
sample.
Magnetization hysteresis curves for decreasing applied field H_a
normally have a maximum at a negative value of H_a when the
average
value of the internal field H_i is close to zero. A paper by L.
Pust
(Praha) et al. reports that vibrating-sample-magnetometer
measurements
on (Bi,Pb)-2223/Ag tapes yield magnetization curves in decreasing
field
that have a maximum at positive values of H_a. The authors explain
this
as an effect of trapped intergranular fields on the value of the
local
magnetic field at the circumference of flat, well-oriented grains in
the
tape. While in most of the sample H_i reaches zero after H_a does,
at
the grain circumference (the bottleneck for intergranular currents)
H_i
reaches zero before H_a does.
The transport critical currents and ac susceptibility of
superconducting
Bi-2223/Ag tapes have been measured by J. Horvat et al.
(Wollongong)
using magnetic fields perpendicular to the tape plane. Three
regimes
were found in log I_c vs. H. At 77 K, log I_c vs. H has negative
curvature for H < 100 mT, positive curvature for 100 mT < H
< 350 mT,
and straight-line behavior for H > 350 mT. The authors attribute
these
regimes to weak links, flux creep, and flux flow, respectively. Both
ac
susceptibility and I_c vs. H show that flux pinning improves with
cold-
pressing and deteriorates with hot-pressing.
A preprint by M. V. Indenbom (EPFL and Chernogolovka) et al. reports
a
correlation of twins on the basal surface of flux-grown
Bi2Sr2CaCu2O8+d
(Bi-2212) single crystals with surface growth steps, the b axis
being
perpendicular to the steps and thus parallel to the growth
direction.
Other Cuprates
A preprint by H. Sato and M. Naito (NTT) reports that (001)
La1.85Sr0.15CuO4 thin films on LaSrAlO4 substrates exhibit a
zero-
resistance Tc as high as 44 K, which is significantly higher than
that
of bulk samples of the same material under ambient pressure. The
increase in Tc is evidently due to the plane stress produced by
the
lattice mismatch between the films and substrates, which compresses
the
a axis of the films but expands the c axis. The authors suggest
that
both compression of the a axis and expansion of the c axis are
important
in increasing Tc.
Computer simulation techniques have been used by S. D'Arco and M.
S.
Islam (Surrey) to investigate the defect and dopant properties of
the
oxyfluoride superconductor Sr2CuO2F2+d. The results confirm that
oxidation involving fluorine incorporation at interstitial sites is
the
most favorable process to introduce the holes necessary for
superconductivity.
A preprint by M.-H. Julien et al. (Grenoble) reports measurements of
the
[63]^Cu and [199]^Hg NMR spectra, nuclear spin-lattice relaxation
rate
(1/T_1), and Cu NQR spectrum in a HgBa2CaCu2O6+d (Hg-1212) powder
sample
with Tc = 101 K. The results agree with previous NMR studies in
the
overdoped regime of the cuprates, showing antiferromagnetic
correlations
and no spin-gap behavior in the normal state.
Three oxygen-deficient phases of LaCuO3-y have been isolated and
investigated by M. Karppinen (Tokyo Institute of Technology and
Helsinki
University of Technology) et al. These materials are of interest
because they have been considered as possible candidates for
superconductivity when optimally doped, and because one of the
members
(y = 0.5) has a two-legged ladder structure.
Applications
An integrated magnetometer combining inductance matching by a
flux
transformer with the low inductance of a multiloop pickup coil has
been
developed by R. Scharnweber and M. Schilling (Hamburg). A 90 pH
dc
SQUID with a five-turn flux transformer was coupled to a
multiloop
pickup coil resulting in an effective magnetometer area of 1.4 mm^2
on a
10 x 10 mm^2 substrate. The SQUID uses ramp-type YBa2Cu3O7-d
Josephson
junctions with PrBa2Cu3O7-d barriers. The 1/f flux noise of the
integrated magnetometer could be suppressed by operation in a
flux-
locked-loop mode with bias-current modulation. At 77 K, the flux-
density noise was measured to be sqrt-S_B(1Hz) = 100 fT/sqrt-Hz.
A related preprint by A. Lewalter et al. (Hamburg) examines the
source
of noise in the above junctions. The authors find that
critical-current
fluctuations are the most important noise source at frequencies in
the
range 1-100 Hz. A flux-noise level of sqrt-S_[phi](1Hz) = 26 mu-
phi_0/sqrt-Hz was measured at 81 K.
An 11 T liquid-helium-free superconducting magnet operating at 6 K
in
vacuum using high-temperature-superconducting current leads has
been
developed by K. Watanabe (Tohoku) et al. The Bi2Sr2Ca2Cu3O10+d
(Bi-
2223) current leads, having tubular shape of 23 mm outer diameter, 20
mm
inner diameter, and 190 mm length, were fabricated by a
powder-sintering
process and a cold isostatic pressing technique. The main heat load
is
not due to the Bi-2223 current leads, which have a thermal
conductivity
about a factor of 500 less than that of copper leads, but instead due
to
Joule heating via contact resistance between the external copper
leads
and the Bi-2223. The NbTi/Nb3Sn coil was conductively cooled from
room
temperature to 4.1 K in 40 h by two 4 K GM-cryocoolers. A field of
10.5
T was held continuously for 24 h at a constant coil temperature of
4.8
K. A central field of 10.7 T in a 52 mm room-temperature bore could
be
generated at an operating current of 149 A.
Theory
A preprint by A. E. Koshelev (Argonne and ISSP-Chernogolovka)
relates
the frequency of the microwave plasma resonance in layered
superconductors to the frequency-dependent current response along the
c
direction. The author demonstrates that a sharp resonance can
persist
even when low-frequency superconducting coherence along the c
direction
is lost, provided the resonance frequency is higher than the
typical
frequency of interlayer phase slips. In this situation, the
plasma
frequency is determined by the average Josephson energy, which
the
author calculates using a high-temperature expansion.
The depinning of a massive elastic string from a linear defect under
the
action of a small driving force, a problem related to the creep
of
vortices trapped by columnar defects or twin boundaries, has been
considered theoretically by M. A. Skvortsov (Landau Institute and
ETH-
Zurich). The author uses the instanton method to calculate the
decay
rate to exponential accuracy and then accounts for fluctuations of
the
quasiclassical solution to determine the pre-exponential factor.
The
decay rate is found to exhibit a kind of first-order transition
from
quantum tunneling to thermal activation with vanishing crossover
region.
A preprint by M. E. Flatte (Iowa) and J. M. Byers (NRL) reports a
calculation of the electronic structure near a single classical
magnetic
impurity in a superconductor using a fully self-consistent
Koster-Slater
algorithm. Within the energy gap, the authors find localized
excited
states, which come in pairs and whose energies are fully
particle-hole
symmetric. The spatial structure of the local density of states,
however, can differ strongly for the two localized states of each
pair.
The authors also present an approximate model, whose analytic
solutions
qualitatively reproduce the key features of the numerical
results.
The low-temperature lattice anharmonicity and its effect on the
electron-phonon ground state in the high-temperature
superconductors
have been examined by T. Hakioglu and H. Tuereci (Bilkent). Using
the
anharmonic elastic continuum model, the authors extracted the third-
and
fourth-order anharmonic coupling constants for YBa2Cu3O7-d and
several
other high-Tc compounds from measured elastic constants. The
authors
find that the anharmonic contribution to the lattice potential is
unusually high for all the examined high-Tc compounds. The
authors
argue that strongly anharmonic phonons in turn lead to
fluctuating
polarons in the electron-phonon ground state and to enhanced
superconducting Tcs.
The exact eigenvalues of the U == U_0N --> infinity Hubbard model
with
long-range hopping, t_[ij] = t for all pairs i not equal to j =
1,
2,..., N, have been found by C. B. Li and D. C. Mattis (Utah) for
arbitrary N. The authors explore the distribution of eigenvalues in
the
limit N --> infinity with J_0 == 4t^2/U_0 finite, and obtain
some
thermodynamic properties of the model.
Using the time-dependent Ginzburg-Landau (TDGL) equations, S. J.
Di
Bartolo and A. T. Dorsey (Virginia) have studied the propagation
of
superconducting-normal planar fronts in superconductors, which
would
appear after a quench to zero applied magnetic field. The
numerical
solutions show that the fronts propagate at a unique speed that
is
controlled by the amount of magnetic flux trapped in the front.
For
small flux, the speed can be determined from the linear marginal
stability hypothesis, and for large flux, the speed may be
calculated
using matched asymptotic expansions. For kappa = 1/sqrt-2, when
the
TDGL equations can be solved exactly, the order parameter and
vector
potential are dual. The exact solution can be used as the
starting
point for a perturbative analysis.
Josephson Junction Arrays
A preprint by E. B. Harris and J. C. Garland (Ohio State) analyzes
a
modified linear Josephson junction array in which additional
unbiased
junctions are used to greatly enhance phase locking. This
geometry
exhibits strongly correlated behavior, with an external magnetic
field
tuning the voltage splay angle between adjacent Josephson
oscillators.
As reported by M. Basler et al. (Jena), a recently proposed scheme
for
the analytical treatment of the dynamics of two-dimensional
hybrid
Josephson junction arrays has been extended to a class of
generalized
hybrid arrays with horizontal shunts involving both a capacitive and
an
inductive component. This class of arrays is of special interest,
because the internal cell coupling favors in-phase synchronization
for
certain parameter values.
A detailed simulation of a Josephson junction array in the presence
of a
varying external field and a transport current has been carried out
by
M. Chandran and P. Chaddah (Indore). The authors find that the
magnetic-field profiles in the array are similar to the profiles
generated by the critical-state model for an infinite slab of hard
type-
II superconductor.
Other Activities
As reported by J. D. Hettinger et al. (Argonne), a pronounced new
dissipation peak in niobium-amorphous silicon (Nb-alpha-Si)
multilayers
as a function of magnetic-field orientation has been observed when
the
interplanar coupling is strong. The dependence of this peak upon
current, anisotropy, and magnetic field differs from that of the
usual
dissipation in layered anisotropic superconductors, which is also
seen.
The new peak is most easily visible for thin alpha-Si layers and
is
consistent with a crossover from 3D to 2D vortex behavior as the
field
direction approaches the plane of the layers.
Electrical transport measurements on the anisotropic organic
superconductor kappa--(BEDT-TTF)2Cu(NCS)2 have been carried out by
S.
Friemel et al. (Orsay) using external magnetic fields applied at
different angles relative to the superconducting layers. By
measuring
the in-plane resistivity versus temperature, the authors obtained
the
angular dependence of the activation energy for thermally activated
flux
flow. The authors also measured the critical current density as a
function of angle. The data can be fitted using the anisotropic
effective mass model with an anisotropy parameter gamma- =
xi_[ab]/xi_c
~~ 10-110.
A publication by E. Podkletnov and R. Nieminen [Physica C 203,
441
(1992)] interpreted their experimental observations in terms of a
shielding of the gravitational interaction by a superconducting disk.
A
preprint by C. S. Unnikrishnan (TIFR-Bombay) examines these
experiments
and concludes that the reported results are inconsistent with the
hypothesis of gravitational shielding. The author also did some
preliminary experiments and found no evidence for the reported
shielding
effect.
Overviews
A review chapter by D. Drung (PTB-Berlin) describes the development
of
SQUID read-out electronics for biomagnetic multichannel systems.
The
author describes and compares concepts using multiple SQUIDs,
SQUIDs
with additional positive feedback, relaxation oscillation SQUIDs,
and
digital SQUIDs. The author discusses both the noise and dynamic
behavior, and presents a model for the achievable speed of a
directly
coupled feedback loop without flux modulation (112 refs.).
Phase-diagram investigations in the quaternary Y-Ba-Cu-O system
have
been critically reviewed by G. Krabbes et al. (Dresden). Included
are
the univariant melt reactions at 2.1 MPa oxygen pressure and the
stability field of YBa2Cu3O7-d as a function of the oxygen
partial
pressure, temperature, and oxygen content in the melt. The
authors
emphasize that knowledge of phase relations is a useful basis for
single-crystal growth, preparation of textured samples, detection
of
impurities, and estimation of the influence of containment materials
(73
refs.).
As stressed in a review article by M. Murakami et al.
(SRL-ISTEC),
unlike Y, which forms only the stoichiometric compound YBa2Cu3O7-d
(Y-
123), the light rare-earth elements (LRE) La, Nd, Sm, Eu, and Gd
usually
form a solid solution, LRE1+xBa2-xCu3O7-d, and when La-123, Nd-123,
and
Sm-123 are melt-processed in air, the presence of this solid
solution
causes a depression in the superconducting transition temperature
Tc.
The authors recently found, however, that the Tcs of these
LRE-123
superconductors were greatly enhanced when these materials were
melt-
processed in a reduced oxygen atmosphere. Moreover, the Jcs of
these
superconductors were larger than that of a good-quality Y-123
superconductor in high magnetic fields at 77 K. In this review,
the
authors report melt-processing methods, microstructural results,
and
superconducting properties for the LRE-123 superconductors, and
they
discuss the flux-pinning mechanisms in these materials (68
refs.).
A summary of progress in the processing and fabrication of mono-
and
multifilamentary silver-sheathed powder-in-tube (PIT) Bi-2223 and
Bi-
2212 conductors has been prepared by U. Balachandran (Argonne) et
al.
Multicore tapes as long as 1,260 m have been fabricated and found
to
have uniform electrical properties. Prototype magnetic coils,
transformers, motors, and power transmission cables have been
demonstrated with such tapes, while progress continues to be made
in
improving the basic properties of the tapes (59 refs.).
A preprint by E. B. Sonin (Helsinki University of Technology and
St.
Petersburg) presents a theoretical overview of the controversial
subject
of the forces on a vortex transverse to its velocity. In the
author's
point of view, three forces contribute to the effective Magnus force
in
general: the superfluid Magnus force, the Iordanskii force, and
the
Kopnin-Kravtsov force. The author presents a critique of the
approaches
used by other authors (55 refs.).
A paper by H. Yamauchi (Tokyo Institute of Technology) and M.
Karppinen
(Helsinki University of Technology) reviews and discusses the
structures
and classification of the existing cuprate families. The authors
emphasize the synthesis and optimization of the series 01(n-1)n,
02(n-
1)n, Cu-12(n-1)n, and Pb-12(n-1)n (53 refs.).
A review chapter by J. T. Williams et al. (TCSUH) discusses some
general
properties of high-temperature superconductors (HTS), considers
the
application of these materials in microstrip transmission-line
feed
networks and microstrip patch antennas, and demonstrates how the use
of
HTS materials can improve the gain of microstrip-antenna arrays.
The
authors conclude by summarizing some relevant experiments (49
refs.).
An overview of inelastic neutron-scattering studies of the
crystal-field
interaction in cuprate and borocarbide superconductors has been
prepared
by J. Mesot et al. (PSI-Villigen and ETH-Zurich). The authors present
a
modified version of the point-charge model, which allows a
reasonable
description of the measured spectra. Specific-heat and
normal-state
magnetic susceptibility curves calculated from the resulting
crystal-
field parameters are in excellent agreement with experiment (34
refs.).
Experiments on the persistent photoinduced enhancement of the
Josephson
effect in YBa2Cu3O7-d junctions are reviewed in a paper by A.
Gilabert
(Nice) et al. These experiments show that the critical current and
the
conductivity of the Josephson junctions can be increased after
illumination. This effect is due to photodoping of the
oxygen-depleted
region in the weak link (17 refs.).
Ph.D. Theses
The doctoral thesis of Z. Gong (Trondheim) reports (a) an
investigation
of the electrical properties and interfacial microstructure of
YBa2Cu3O7-d/Ag bilayers for making low-resistance contacts and
superconducting-normal-superconducting (SNS) junctions and (b)
the
fabrication of a 29.13 MHz surface-acoustic-wave (SAW) bandpass
filter
with YBa2Cu3O7-d electrodes on a Y-cut, Z-propagation lithium
niobate
(Y-Z LiNbO3) substrate (163 refs.).
The Strathclyde Ph.D. thesis of L. Hao reports experimental studies
of
the electrical characteristics and noise properties for a variety
of
YBa2Cu3O7-d films and devices: laser-ablated epitaxial films,
laser-
ablated bicrystal junctions on YSZ, sputtered step-edge junctions
on
SrTiO3, laser-ablated bicrystal junctions on MgO, sputtered
step-edge
junctions on MgO, bicrystal junctions and flux-flow amplifiers,
and
biepitaxial SQUIDs (119 refs.)
Contributed by John R. Clem
Contents: Preprints begin on page 6; Coming Events begin on page
14;
Resources are on page 15; and FYI is on page 15.
High-Tc Update is available without charge to interested persons.
Recipients are expected to participate in this information exchange
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sending us preprints, reprints, meeting news, research news, etc.
Contributions to defray the cost of newsletter printing and mailing
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welcome.
PREPRINTS
To obtain a particular preprint, contact the first author at the
address
given at the end of the citation. Help us expand this list by
sending
us your complete preprint. Please specify where and when your paper
was
submitted. An * next to an entry indicates it is a correction or
revision of a previous entry. PACS codes and/or key words are given
at
the end of the citation.
P. Allenspach, M. C. de Andrade, and M. B. Maple, "Oxygen Dependence
of
the Magnetic Rare-Earth Ordering in SmBa2Cu3Ox." Submitted to the
XXI
Int. Conf. on Low Temperature Phys. (LT21), Prague, Czech Republic,
Aug.
8-14, 1996. Laboratory for Neutron Scattering, ETH Zurich and
Paul-
Scherrer-Institut, CH-5232 Villigen PSI, SWITZERLAND; telephone +41
56
310 2527; telefax +41 56 310 2939; e-mail
peter.allenspach@psi.ch.
P. Allenspach, U. Gasser, and A. Furrer, "Magnetic Properties of Co-
and
Cu-Doped RNi2[11]^B2C (R = Ho, Er) Measured by Neutron
Scattering."
Submitted to the Int. Conf. on Strongly Correlated Electron
Systems
(SCES'96), Zurich, Switzerland, Aug. 19-22, 1996; to be published
in
Physica B. Laboratory for Neutron Scattering, ETH Zurich and
Paul-
Scherrer-Institut, CH-5232 Villigen PSI, SWITZERLAND; telephone +41
56
310 2527; telefax +41 56 310 2939; e-mail peter.allenspach@psi.ch.
Key
words: borocarbides, neutron scattering, magnetic properties,
crystal
electric field.
M. K. Al-Mosawi, C. Beduz, Y. Yang, and R. G. Scurlock, "The
Fabrication, Microstructure and Transport Current Study of BPSCCO
2223
Multi-Connected Tapes." To be published in Physica C, Vol. 264
(in
press). Institute of Cryogenics, University of Southampton,
Southampton, SO17 1BJ, UNITED KINGDOM; telefax +44 1703 593 053.
F. M. Araujo-Moreira, W. A. Ortiz, and O. F. de Lima,
"Exponential
Critical State Model Applied to ac Susceptibility Data for the
Superconductor YBa2Cu3O7-d." To be published in J. Appl. Phys.
Departamento de Fisica, Universidade Federal de Sao Carlos, C.P.
676,
13565-905 Sao Carlos, SP, BRAZIL.
V.P.S. Awana, D. A. Landinez, J. M. Ferreira, J. Albino Aguiar,
Rajvir
Singh, and A. V. Narlikar, "Normal State Magnetism of Zn-Doped
and
Oxygen Deficient CaLaBaCu3O7 Superconductor." To be published in
Mod.
Phys. Lett. B., Vol. 10, No. 13. Departamento de Fisica,
Universidade
Federal de Pernambuco, 50670-901 Recife PE, BRAZIL; telefax +55 81
271
0359; e-mail awana@npd.ufpe.br.
U. Balachandran, R. Jammy, M. Chudzik, A. N. Iyer, and P. Haldar,
"Bi-
Based Superconductors: Advances in Processing and
Characterization."
To be published in J. Metals. Energy Technology Division, Argonne
National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439;
telefax
(708) 252-9595; e-mail janice_coble@qmgate.anl.gov.
L. Baril, T. Klein, J. Marcus, and C. Escribe-Filippini, "T, J and
H
Dependence of the Activation Energy in the Vortex Glass Phase of
(K,Ba)BiO3 Single Crystals." Submitted to Phys. Rev. B.
Laboratoire
d'Etudes des Proprietes Electroniques des Solides, Centre National de
la
Recherche Scientifique, BP166, F-38042 Grenoble Cedex 9, FRANCE;
T.
Klein's telephone +33 76 88 10 08; telefax +33 76 88 79 88;
e-mail
klein@lepes.polycnrs-gre.fr. 74.25.Dw; 74.60.Ge; 74.25.Fy.
M. Basler, W. Krech, and K. Yu. Platov, "Theory of Phase-Locking
in
Generalized Hybrid Josephson Junction Arrays." Submitted to Phys.
Rev.
B. Institut fuer Festkoerperphysik,
Friedrich-Schiller-Universitaet
Jena, Max-Wien-Platz 1, D-07743 Jena, GERMANY; e-mail pmb@rz.uni-
jena.de; preprint also available at cond-mat@xxx.lanl.gov
(#9605159).
74.50.+r; 85.25.Dq.
H. Berger, M. Mobarak, and G. Margaritondo, "Growth of Large-Size
C60
Fullerene Single Crystals." To be published in J. Phys. D (in
press).
Institut de Physique Appliquee, Ecole Polytechnique Federale,
CH-1015
Lausanne, SWITZERLAND.
W. Bieger, U. Wiesner, G. Krabbes, P. Schaetzle, A. Bauer, P.
Verges,
and L. Zelenina, "Melt Texturing and Properties Control of
Nd1+yBa2-
yCu3Ox Bulk Materials." Submitted to J. Low Temp. Phys.: Proc. of
the
Int. Conf. on Phys. and Chem. of Molecular and Oxide Supercond.
(MOS'96), Karlsruhe, Germany, Aug. 2-6, 1996. Institut fuer
Festkoerper- und Werkstofforschung e.V., Postfach 270016, D-01171
Dresden, GERMANY.
Gianni Blatter, Mikhail Feigel'man, Vadim Geshkenbein, Anatoli
Larkin,
and Anne van Otterlo, "Electrostatics of Vortices in Type II
Superconductors." Theoretische Physik, ETH-Hoenggerberg, CH-8093
Zurich, SWITZERLAND.
A. V. Bobyl, M. E. Gaevski, S. F. Karmanenko, I. A. Khrebtov, V.
N.
Leonov, D. V. Shantsev, V. A. Solov'ev, and R. A. Suris,
"Magneto-
Depending Noise of a Single Latent Weak Link in YBa2Cu3O7-x Film."
To
be published in Physica C (in press). Solid State Physics, State
Technical University, 29 Polytechnicheskaya, St. Petersburg
195251,
RUSSIA. Key words: weak links, fluctuation phenomena, scanning
electron microscopy, thin films.
Mahesh Chandran and P. Chaddah, "Critical State in a Josephson
Junction
Array: Effect of Transport Currents." To be published in Physica C
(in
press). Low Temperature Physics Group, Center for Advanced
Technology,
Indore 452 013, INDIA. Key words: Josephson junction array,
critical
state. 74.30.-e.
S. D'Arco and M. S. Islam, "Defect and Dopant Properties of the
Oxyfluoride Superconductor, Sr2CuO2F2+d." To be published in Phys.
Rev.
B. Contact M. S. Islam, Department of Chemistry, University of
Surrey,
Guildford, Surrey GU2 5XH, UNITED KINGDOM; telephone +44 1483
300800,
ext. 2596; telefax +44 1483 300803; e-mail m.islam@surrey.ac.uk.
S. John Di Bartolo and Alan T. Dorsey, "Velocity Selection for
Propagating Fronts in Superconductors." Department of Physics,
University of Virginia, McCormick Road, Charlottesville, VA
22901.
C. Di Nallo, F. Mesa, and D. R. Jackson, "Excitation of Leaky Modes
on
Multilayer Stripline." Preprint #96:075; submitted to the Proc. of
the
IEEE MTT Int. Microwave Symp., San Francisco, California, June
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.
Dietmar Drung, "Advanced SQUID Read-Out Electronics." To appear
in
SQUID Sensors: Fundamentals, Fabrication and Applications, NATO
ASI
Series, edited by H. Weinstock (Kluwer Academic Publishers,
Dordrecht,
1996). Physikalisch-Technische Bundesanstalt, Abbestrasse 2-12,
D-10587
Berlin, GERMANY.
T. D. Dzhafarov, M. Altunbas, and O. Goeruer, "High-Temperature
Thermal
Expansion of BiPbSrCaCuO Superconductors." To be published in Physica
C
(in press). Contact M. Altunbas, Department of Physics, Faculty
of
Science and Arts, Karadeniz Technical University, 61080 Trabzon,
TURKEY.
V. F. Elesin, K. E. Kon'kov, A. V. Krasheninnikov, and L. A.
Openov,
"Analysis of Experiments on Ion Irradiation of YBa2Cu3O7-x Films:
d-
Wave Pairing or Anisotropic s-Wave Pairing?" Submitted to JETP
(in
Russian). Contact L. A. Openov, Moscow State Engineering Physics
Institute, Kashirskoe sh.31, 115409 Moscow, RUSSIA; e-mail
opn@supercon.mephi.ru or stk@htsc.msk.su. English version
available.
G. A. Fischer, H. Trammell, S. B. Barlow, R. F. Jardim, and M. S.
Torikachvili, "Electrical Resistivity in Bi2Sr2CaCu2O8+-d
Compounds
Synthesized via Melt Casting." To be published in Physica C (in
press).
Contact M. S. Torikachvili, Department of Physics, San Diego
State
University, San Diego, CA 92182-1233; telefax (619) 594-5485;
e-mail
milton@sciences.sdsu.edu. Key words: electrical resistivity, DTA,
SEM,
weak links.
Michael E. Flatte and Jeff M. Byers, "Local Electronic Structure of
a
Single Magnetic Impurity in a Superconductor." Department of
Physics
and Astronomy, University of Iowa, Iowa City, IA 52242.
S. Friemel, C. Pasquier, and D. Jerome, "Scaling in Angle
Resolved
Electrical Transport Measurements on kappa-(BEDT-TTF)2Cu(NCS)2." To
be
published in the J. Schegolev Memorial Vol. of J. Physique I.
Laboratoire de Physique des Solides, URA 2 CNRS, Universite
Paris-Sud,
Batiment 510, F-91405 Orsay Cedex, FRANCE; telephone +33 1 69 41 53
58;
telefax +33 1 69 41 60 86; e-mail friemel@lps.u-psud.fr.
74.70.Kn;
74.25.Fy; 74.60.Jg.
G. B. Furman, E. M. Kunoff, and S. D. Goren, "Nuclear
Spin-Lattice
Relaxation via Thermal Vortex Motion in Superconductors." To be
published in Physica C (in press). Contact E. M. Kunoff, Department
of
Physics, Ben-Gurion University, Be'er-Sheva, ISRAEL; telefax +972 7
472
903; e-mail esther@ondigo.ac.il. Key words: NMR, non-exponential
spin-
lattice relaxation, spin-lattice relaxation time T_1.
U. Gasser, P. Allenspach, and A. Furrer, "Magnetic Properties of Co-
and
Cu-Doped RNi2[11]^B2C (R = Ho, Er) Measured by Neutron
Scattering."
Presented at the 2nd Int. Summer School on High Temp. Supercond.,
Eger,
Hungary, July 13-20, 1996. Laboratory for Neutron Scattering, ETH
Zurich and Paul-Scherrer-Institut, CH-5232 Villigen PSI,
SWITZERLAND.
A. Gilabert, A. Hoffmann, J. Elly, M. G. Medici, F. Schmidl, P.
Seidel,
and Ivan K. Schuller, "Photoinduced Enhancement of the Josephson
Effect
in YBaCuO Grain Boundary Junctions." To be published in J. Low
Temp.
Phys.: Proc. of the Weak Superconductivity Symp. (WSS'96),
Smolenice,
Slovak Republic, August 4-7, 1996. Contact A. Hoffmann, Department
of
Physics 0350, University of California, 9500 Gilman Drive, La Jolla,
CA
92093-0350; e-mail hoffmann@ucsd.edu. 73.50.Pz; 74.50.+r;
74.72.Bk.
R. E. Gladyshevskii, Ph. Galez, K. Lebbou, J. Allemand, R. Abraham,
M.
Couach, R. Fluekiger, J.-L. Jorda, and M. Th. Cohen-Adad,
"Structural
Characterization and Superconducting Properties of
(Tl0.5Pb0.5)(Sr2-
xBax)Ca2Cu3O9-d." To be published in Physica C (in press).
Departement
de Physique de la Matiere Condensee, Universite de Geneve, 24
quai
Ernest-Ansermet, CH-1211 Geneve 4, SWITZERLAND; telefax +41 22 702
6869.
Key words: Tl,Pb-1223, crystal structure, high-Tc superconductor.
Zhenghong Gong, "Investigation of YBa2Cu3O7-d/Ag Thin Film
Interfaces:
Performance of a Surface Acoustic Wave Filter with YBa2Cu3O7-d
Superconducting Electrodes." Submitted as a Ph.D. thesis
(Norwegian
University of Science and Technology). Institutt for Fysikk
Electronikk, Universitetet i Trondheim, Norges Tekniske Hogskole,
7034
Trondheim-NTH, NORWAY.
M. Gutmann, P. Allenspach, F. Fauth, A. Furrer, A. Hewat, and S.
Rosenkranz, "Neutron Investigation of Nd2-x-yCexLayCuO4
(0<=x<=0.2;
y=0.5, 1)." To be presented at the Int. Conf. on Physics and
Chemistry
of Molecular and Oxide Superconductors (MOS'96), Karlsruhe,
Germany,
Aug. 2-6, 1996; to be published in J. Low Temp. Phys. Laboratory
for
Neutron Scattering, ETH Zurich and Paul-Scherrer-Institut,
CH-5232
Villigen PSI, SWITZERLAND. 28.20.Cz; 61.66.Fn; 74; 74.62.-c;
74.72.Jt.
T. Hakioglu and H. Tuereci, "Anharmonic Phonons and Correlated
Polarons
in High Temperature Superconductivity." Department of Physics,
Bilkent
University, Bilkent, Ankara TR-06533, TURKEY; telefax +90 321 266
4579;
e-mail hakioglu@trbilun.bitnet.
*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). Contact S. Awaji, HFLSM, Institute for Materials
Research,
Tohoku University, Sendai 980-77, JAPAN; e-mail
f22124@cctu.cc.tohoku.ac.jp. *New contact information.
G. C. Han, K. Watanabe, S. Awaji, N. Kobayashi, M. Takeo, K. Kimura,
and
M. Hashimoto, "High-Field Studies on Peak Effect of
Quench-Melt-Growth
Processed YBa2Cu3O7." Presented at the Eighth Int. Workshop on
Critical
Currents in Supercond., (8th IWCC), Kitakyushu, Japan, May 27-29,
1996.
Contact S. Awaji, HFLSM, Institute for Materials Research, Tohoku
University, Sendai 980-77, JAPAN; e-mail f22124@cctu-
mail.cc.tohoku.ac.jp.
Ling Hao, "Excess Noise in YBa2Cu3O7 Thin Film Grain Boundary
Josephson
Junctions and Devices." Submitted as a Ph.D. thesis (University
of
Strathclyde). Department of Physics and Applied Physics, John
Anderson
Building, University of Strathclyde, 107 Rottenrow, Glasgow G4
0NG,
Scotland, UNITED KINGDOM; telephone +44 141 552 4400; telefax +44
141
552 2891.
W. Harneit, T. Klein, C. Escribe-Filippini, H. Rakoto, J. M. Broto,
A.
Sulpice, R. Buder, J. Marcus, and W. Schmidbauer, "Short Time Study
of
the Fishtail Effect in Ba0.6K0.4BiO3 Single Crystals." To be
published
in Physica C. Laboratoire d'Etudes des Proprietes Electroniques
des
Solides-CRNS, B.P. 166, F-38042 Grenoble-Cedex 9, FRANCE. Key
words:
oxide superconductors, fishtail effect, collective pinning,
delta-Tc
pinning.
E. B. Harris and J. C. Garland, "Voltage Splay Modes and Enhanced
Phase
Locking in a Modified Linear Josephson Array." Department of
Physics,
Ohio State University, Columbus, OH 43210. 74.40.+k; 74.50.+r;
05.45.+b.
Masashi Hasegawa, Yoshitaka Matsushita, and Humihiko Takei,
"Local
Structural Changes in Tl2Ba2Ca2Cu3O10 Single Crystal Between 90 K
and
290 K." To be published in Physica C (in press). Institute for
Solid
State Physics, University of Tokyo, 7-22-1 Roppongi, Minato-ku,
Tokyo
106, JAPAN.
T. Haugan, S. Patel, and D. T. Shaw, "A Study of Bubble-Defect
Formations in Ag-Sheathed Bi2Sr2CaCu2O8+x (Bi-2212)
Superconducting
Tapes." To be published in Physica C (in press). New York State
Institute on Superconductivity and Department of Electrical and
Computer
Engineering, State University of New York at Buffalo, Buffalo, NY
14260-
1900; telefax (716) 645-3349; e-mail haugan@acsu.buffalo.edu. Key
words: Ag sheathed Bi2Sr2CaCu2O8+x tapes, bubble defects,
solid-state
and spray-roasted powder, carbon impurities.
J. D. Hettinger, B. R. Washburn, N. B. Remmes, D. G. Steel, K. E.
Gray,
Eric E. Fullerton, and C. H. Sowers, "Unusual Vortex Dynamics in
Nb-
alpha-Si Multilayers with Strong Interlayer Coupling." Submitted
to
Phys. Rev. Lett. Materials Science Division, Argonne National
Laboratory, 9700 South Cass Avenue, Argonne, IL 60439; telefax
(708)
252-9595; e-mail janice_coble@qmgate.anl.gov. 74.80.Dm; 74.60.Jg;
74.60.Ec; 74.25.Fy.
Z. Hiroi, N. Kobayashi, and M. Takano, "Synthesis, Structure, and
Superconductivity of Ca2-xNaxCuO2Cl2." To be published in Physica C
(in
press). Institute for Chemical Research, Kyoto University, Uji,
Kyoto-
fu 611, JAPAN; telefax +81 774 32 3419. Key words:
copper-oxychloride
superconductor, high-pressure synthesis, apical oxygen.
J. Horvat, S. X. Dou, H. K. Liu, and R. Bhasale, "Critical Currents
at
Elevated Fields in Ag/BSCCO Tapes." Submitted to the Eighth Int.
Workshop on Critical Currents in Supercond., (8th IWCC),
Kitakyushu,
Japan, May 27-29, 1996. Centre for Superconducting and Electronic
Materials, University of Wollongong, Wollongong 2522 AUSTRALIA;
e-mail
jhorvat@uow.edu.au.
C. Y. Huang, J. G. Lin, C. W. Chu, and J. C. Ho, "High Pressure
and
Transport Properties on Some High-Tc Superconductors." Preprint
#96:073; submitted to the Proc. of the Int. Conf. on Advanced
Materials
Devices (ICAMD'96), Phoenix Park, Korea, June 11-13, 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.
M. V. Indenbom, C. J. van der Beek, V. Berseth, M. Konczykowski,
N.
Motohira, H. Berger, and W. Benoit, "Pinning in BSCCO above the
Ordinary
Irreversibility Line." To be published in J. Low Temp. Phys.: Proc.
of
the Int. Conf. on Phys. and Chem. of Molecular and Oxide
Supercond.
(MOS'96), Karlsruhe, Germany, Aug. 2-6, 1996. Institut de Genie
Atomique, Ecole Polytechnique Federale de Lausanne, CH-1015
Lausanne,
SWITZERLAND; telephone +41 21 693 44 98; telefax +41 21 693 44 70;
e-
mail indenbom@igahpse.epfl.ch. 74.60.Ec; 74.60.Ge; 74.25.Dw;
74.72.Hs.
M. V. Indenbom, C. J. van der Beek, V. Berseth, Th. Wolf, H. Berger,
T.
W. Li, and W. Benoit, "Morphology of Growth of Bi2Sr2CaCu2O8
Single
Crystals." To be published in J. Low Temp. Phys.: Proc. of the
Int.
Conf. on Phys. and Chem. of Molecular and Oxide Supercond.
(MOS'96),
Karlsruhe, Germany, Aug. 2-6, 1996. Institut de Genie Atomique,
Ecole
Polytechnique Federale de Lausanne, CH-1015 Lausanne,
SWITZERLAND;
telephone +41 21 693 44 98; telefax +41 21 693 44 70; e-mail
indenbom@igahpse.epfl.ch. 74.62.Bf; 74.25.Gz; 74.72.Hs.
A. V. Inyushkin, A. N. Taldenkov, and T. G. Uvarova, "Thermal
Conductivity of Oxygen-Deficient YBa2Cu3O6+x." To be published in
Phys.
Rev. B. Fakultaet fuer Physik und Geowissenschaften, Universitaet
Leipzig, Linnestrasse 5, D-04103 Leipzig, GERMANY; telefax +49 341 97
32
769; e-mail inyushki@rz.uni-leipzig.de. 66.70.+f; 72.15.Eb;
74.25.Fy;
74.72.Bk.
Ch. Jooss, A. Forkl, R. Warthmann, H.-U. Habermeier, B. Leibold, and
H.
Kronmueller, "Thickness and Roughness Dependence of Magnetic Flux
Penetration and Critical Current Densities in YBa2Cu3O7-d Thin
Films."
To be published in Physica C (in press). Contact H. Kronmueller,
Max-
Planck-Institut fuer Metallforschung, Heisenbergstrasse 1,
D-70569
Stuttgart, GERMANY; telefax in Switzerland +41 1 633 10 77.
M.-H. Julien, M. Horvatic, P. Carretta, C. Berthier, Y. Berthier,
P.
Segransan, S. M. Loureiro, and J.-J. Capponi, "[63]^Cu and [199]^Hg
NMR
in Overdoped HgBa2CaCu2O6+d." To be published in Physica C.
Grenoble
High Magnetic Field Laboratory, CNRS/MPI-FKF, BP 166, F-38042
Grenoble
Cedex 9, FRANCE; telefax +33 76 85 56 10; e-mail
mjulien@labs.polycnrs-
gre.fr. Key words: NMR, NQR, spin-lattice relaxation time T_1,
spin
fluctuations. 74.25.Nf; 74.72.Gr; 76.60.-k.
M. Karppinen, H. Yamauchi, H. Suematsu, and O. Fukunaga, "Synthesis
and
Characterization of LaCuO3-y Phases with Various Oxygen Contents."
To
be published in Superlattices and Microstructures. Materials and
Structures Laboratory, Tokyo Institute of Technology, 4259
Nagatsuta,
Midori-ku, Yokohama 226, JAPAN; telephone +81 45 924 5315; telefax
+81
45 921 6953; e-mail yamauchi@materia.titech.ac.jp.
V. A. Kashurnikov and Yu. G. Kharchenko, "Density of States and
Quasiparticle Dispersion in Emery Model: Nonlocal World-Line
Monte
Carlo Algorithm." To be published in JETP Lett., Vol. 63.
Department
of Physics and Technical Application of Superconductivity, Moscow
State
Engineering Physics Institute, Kashirskoe Sh. 31, 115409 Moscow,
RUSSIA;
telephone +7 095 324 10 81; telefax +7 095 324 21 11; e-mail
kash@supercon.mephi.ru. Key words: Emery model, density of
states,
Monte Carlo, quasiparticle dispersion. 74.20.Mn. Preprint in
Russian,
English version available.
T. Kawahara, T. Suzuki, E. Komai, K. Nakazawa, T. Terashima, and
Y.
Bando, "Electric-Field Effect on Transport and Superconducting
Properties of YBa2Cu3O7-x." To be published in Physica C (in
press).
Department of Physics, Kyoto University, Kyoto 606-01, JAPAN. Key
words: thin films, electric resistivity, flux pinning, applications
of
high-Tc superconductors, hole concentration.
T. Kawashima and E. Takayama-Muromachi, "Superconductivity in the
Series
of Compounds Sr2Can-1CunOy (n = 1-4) Prepared under High Pressure."
To
be published in Physica C (in press). National Institute for
Research
in Inorganic Materials, 1-1 Namiki, Tsukuba, Ibaraki 305, JAPAN;
telefax
+81 295 527449. Key words: Sr2Can-1CunOy, high-pressure
synthesis,
magnetic susceptibility.
Michael R. Koblischka, Ladislav Pust, and Milos Jirsa, "Formation of
the
Central Peak in Magnetization Loops of Type-II Superconductors." To
be
presented at the XXI Int. Conf. on Low Temperature Physics
(LT21),
Prague, Czech Republic, Aug. 8-14, 1996; to be published in
Czechoslovak
J. Phys., Vol. 46. Contact Ladislav Pust, Institute of Physics,
Academy
of Sciences of the Czech Republic, Na Slovance 2, CZ-18040 Praha
8,
CZECH REPUBLIC; telephone +42 2 6605-2617; telefax +42 2 82 1227;
e-mail
pust@fzu.cz. Key words: magnetic hysteresis loops, HTS, single
crystals, superconducting currents.
A. E. Koshelev, "Plasma Resonance and Remaining Josephson Coupling
in
the 'Decoupled Vortex Liquid Phase' in Layered Superconductors."
Submitted to Phys. Rev. Lett. Materials Science Division, Argonne
National Laboratory, 9700 South Cass Avenue, Argonne, IL 60439;
telefax
(708) 252-9595; e-mail janice_coble@qmgate.anl.gov; preprint also
available at cond-mat@xxx.lanl.gov (#9605067).
G. Krabbes, W. Bieger, P. Schaetzle, and U. Wiesner, "Phase
Equilibria:
A Fundamental for Growth and Processing of Y-Ba-Cu-O and Related
High
Temperature Superconductors." To be published in Current Topics
in
Crystal Growth Research, edited by C.S.I., Trivandrum, India.
Institut
fuer Festkoerper- und Werkstofforschung e. V., Postfach, D-01171
Dresden, GERMANY.
Pramada Lele and Arun S. Nigavekar, "Interface Mechanism of
Co/BiSrCaCuO
System Studied by XPS and UPS Techniques." To be published in
Physica
C, Vol. 264 (in press). Department of Physics, University of Pune,
Pune
411 007, INDIA.
A. Lewalter, F. Ludwig, D. Reimer, and M. Schilling, "Temperature
Dependence of Noise Properties of Directly Coupled YBa2Cu3O7
Magnetometers with PrBa2Cu3O7 Ramp-Type Josephson Junctions." To
be
published in Physica C. Institut fuer Angewandte Physik und
Zentrum
fuer Mikrostrukturforschung, Universitaet Hamburg, Jungiusstrasse 11,
D-
20355 Hamburg, GERMANY. 85.25.Dq; 85.25.Am; 74.72.-h.
C. B. Li and D. C. Mattis, "Hubbard Model with Long-Ranged
Hopping."
Department of Physics, University of Utah, Salt Lake City, UT
84112.
S. T. Li, A. Ritzer, E. Arenholz, D. Baeuerle, W. M. Huber, H.
Lengfellner, and W. Prettl, "Step-Like Growth of Bi2Sr2CaCu2O8 Films
on
Off-Axis Oriented (001) SrTiO3." Submitted to Appl. Phys. A.
Angewandte Physik, Johannes-Kepler-Universitaet, A-4040 Linz,
AUSTRIA;
telefax +43 732 2468 9242; e-mail shutao.li@jk.uni-linz.ac.at.
81.15.-
z; 68.55; 74.70.
Y. H. Li and J. L. MacManus-Driscoll, "Identification of High
Pressure
Phase in Bi-Sr-Ca-Cu-O Superconductors by HRTEM and XRD." To be
published in Physica C (in press). Department of Materials,
Imperial
College, London SW7 2BP, UNITED KINGDOM; telefax +44 171 584
3194.
H. Luetgemeier, S. Schmenn, P. Meuffels, O. Storz, R. Schoellhorn,
Ch.
Niedermayer, I. Heinmaa, and Yu. Baikov, "Different Type of the
Oxygen
Order in the REBa2Cu3O(6+x) H-Tc Superconductors with Different RE
Ionic
Radii." To be published in Physica C (in press). KFA
Forschungszentrum, Juelich IFF, GERMANY; e-mail h.lutgemeier@kfa-
juelich.de.
S. Madhavan, J. A. Mitchell, T. Nemoto, S. Wozniak, Ying Liu, D.
G.
Schlom, A. Dabkowski, and H. A. Dabkowska, "Growth of Epitaxial
Sr2RuO4
Films and YBa2Cu3O7-d/Sr2RuO4 Heterostructures." Submitted to the
10th
American Conf. on Crystal Growth and 9th Int. Conf. on Vapor Growth
&
Epitaxy (ACCG-10), Vail, Colorado, Aug. 5-9, 1996; to be published
in
the J. Cryst. Growth. Department of Materials Science and
Engineering,
Pennsylvania State University, University Park, PA 16802.
Atsutaka Maeda, Song Sakamoto, Tetsuo Hanaguri, Hiroshi Ikeda, and
Ryozo
Yoshizaki, "Josephson-Plasma Resonance of Bi-Cuprates." Submitted
to
the Proc. of the XXI Int. Conf. on Low Temperature Physics
(LT21),
Prague, Czech Republic, Aug. 8-14, 1996. Department of Basic
Science,
University of Tokyo, 3-8-1 Komaba, Meguro-ku, Tokyo 153, JAPAN.
S. Malo, D. Pelloquin, A. Maignan, C. Michel, M. Hervieu, and B.
Raveau,
"Superconducting Oxycarbonates Hg1-xVxSr4-yBayCu2O7-dCO3: Three
Closely
Related Structural Families." To be published in Physica C (in
press).
Contact C. Michel, Laboratoire de Cristallographie et Sciences
des
Materiaux, ISMRA-Universite de Caen, Boulevard du Marechal Juin,
F-14050
Caen Cedex, FRANCE.
J. Mesot, P. Allenspach, U. Gasser, and A. Furrer, "Crystal Field
Excitations in Cuprate and Boron Carbide." Presented at the 21st
Rare
Earth Res. Conf. (21st RERC), Duluth, Minnesota, July 7-12, 1996; to
be
published in J. Alloys & Compounds. Laboratory for Neutron
Scattering,
Paul Scherrer Institut and ETHZ, CH-5232 Villigen PSI,
SWITZERLAND;
telefax +41 56 310 29 39; e-mail mesot@psi.ch. Key words: neutron
spectroscopy, crystal field, cuprate, boron carbide,
superconductivity.
I. Monot, J. Wang, M. P. Delamare, J. Provost, and G. Desgardin,
"Influence of Different Melt Processings upon the Microstructure
and
Critical Current of Textured Y123." To be published in Physica C
(in
press). Laboratoire CRISMAT, ISMRA and University Caen 6, Boulevard
du
Marechal Juin, F-14050 Caen Cedex, FRANCE; telefax +33 31 951600.
81.10.Fq; 74.60.Mj; 74.10.Vy; 61.50.Jr.
A. A. Moolenaar, P.C.M. Gubbens, J. J. van Loef, M.J.V. Menken, and
A.
A. Menovsky, "PrBa2Cu3O7 Investigated by [141]^Pr Mossbauer
Spectroscopy." To be published in Physica C (in press). Contact
P.C.M.
Gubbens, Interfacultair Reactor Instituut, TU Delft, Mekelweg 15,
2629
JB Delft, THE NETHERLANDS; telefax +31 15 786422; e-mail
gubbens@iri.tudelft.nl. Key words: PrBa2Cu3O7, high-Tc
superconductors, perovskites, magnetization, rare earths,
Mossbauer
spectroscopy.
M. Murakami, N. Sakai, T. Higuchi, and S. I. Yoo, "Melt Processed
LRE-
Ba-Cu-O." To be published in Supercond. Sci. & Technol.
Superconductivity Research Laboratory, International
Superconductivity
Technology Center (ISTEC), 1-16-25 Shibaura, Minato-ku, Tokyo
105,
JAPAN.
Masaru Nakamura, Makoto Kambara, Takateru Umeda, and Yuh
Shiohara,
"Effect of Oxygen Partial Pressure for the Neodymium Solubility in
Ba-
Cu-O Solvent." 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.
O. Narikiyo, "Itinerant-Localized Duality Description of the
Normal
State of High-Tc Cuprates: Incoherent Spectra near the Mott
Transition." To be published in Physica C (in press). Department
of
Material Physics, Faculty of Engineering Science, Osaka
University,
Toyonaka, Osaka 560, JAPAN.
P. P. Newcomer, J. C. Barbour, L. M. Wang, E. L. Venturini, J. F.
Kwak,
R. C. Ewing, M. L. Miller, and B. Morosin, "Temperature Dependent
Microstructural Modification in Ion-Irradiated Tl-Type High
Temperature
Superconductors." To be published in Physica C (in press). Sandia
National Laboratories, Albuquerque, NM 87185; telefax (505) 844-4045;
e-
mail ppnewco@sandia.gov.
N. G. Patil, Subir Saha, S. S. Banerjee, K. Ghosh, S. Ramakrishnan,
A.
K. Grover, T. V. Chandrasekhar Rao, G. Ravikumar, P. K. Mishra, V.
C.
Sahni, E. Yamamoto, Y. Haga, M. Hedo, Y. Inada, and Y. Onuki,
"Multiple
Peak Structure in the Peak Effect Region of the Vortex Lattice in
the
Cubic Superconductor CeRu2." Preprint #TIFR/CM/96-101(II); submitted
to
Phys. Rev. Lett. Tata Institute of Fundamental Research, Homi
Bhabha
Road, Bombay 400 005, INDIA; telefax +91 22 215 2110/2181; e-mail
pnitin@tifrc3.tifr.res.in. Key words: peak effect, FFLO state,
flux-
lattice melting. 64.70.Dv; 74.25.Ha; 74.60.Ge; 74.70.Tx.
V. Psycharis, C. Mitros, A. Koufoudakis, H. Gamari-Seale, D.
Niarchos,
N. Kalitsounakis, N. Poulakis, D. Palles, and E. Liarokapis,
"Structural
Study, Resistivity, Magnetization and Raman Measurements for the
HTc
Superconducting Compounds SmBa2-xSrxCu3O6+y (x = 0.0, 0.25, 0.5,
0.75,
1.0 and 1.25)." To be published in Physica C (in press). Institute
of
Materials Science, N.C.S.R. 'Demokritos', 153 10 Aghia Paraskevi,
Attiki, GREECE; telefax +30 1 651 9430. Key words:
SmBa2-xSrxCu3O6+y,
HTc superconductors, O-T transition, charge redistribution, Raman
scattering.
Ladislav Pust, Alexander Galkin, and Michael R. Koblischka, "Shape
of
Magnetic Hysteresis Loop Measured on Superconducting Bi-2223/Ag
Tapes."
To be presented at the XXI Int. Conf. on Low Temperature Phys.
(LT21),
Prague, Czech Republic, Aug. 8-14, 1996; to be published in
Czechoslovak
J. Phys., Vol 46 (1996). Institute of Physics, Academy of Sciences
of
the Czech Republic, Na Slovance 2, CZ-18040 Praha 8, CZECH
REPUBLIC;
telephone +42 2 6605-2617; telefax +42 2 82 1227; e-mail
pust@fzu.cz.
Key words: magnetic hysteresis loops, (Bi,Pb)-2223/Ag tapes,
superconducting currents.
V. Rouessac, J. Wang, J. Provost, and G. Desgardin, "Processing
and
Superconducting Properties of Highly Textured Bi(Pb)-2223 Ceramics
by
Sinter-Forging." To be published in Physica C. Laboratoire
CRISMAT,
ISMRA, CRNS URA 1318, University of Caen, 6 Bd. du Marechal Juin,
F-
14050 Caen, FRANCE.
Seungoh Ryu, M. Hellerqvist, S. Doniach, A. Kapitulnik, and D.
Stroud,
"Dynamical Phase Transition in a Driven Disordered Vortex
Lattice."
Department of Physics, Ohio State University, Columbus, OH 43021;
e-mail
ryu@pacific.mps.ohio-state.edu or
http://www.physics.ohio-
state.edu:80/~ryu/.
S. V. Samoylenkov, O. Yu. Gorbenko, and A. R. Kaul,
"Superconducting
Properties of Oxygen Deficient LuBa2Cu3O7-x Thin Films." To be
published in Physica C (in press). Department of Chemistry,
Moscow
State University, 119899 Moscow, RUSSIA.
Susumu Sasaki, Azusa Matsuda, and C. W. Chu, "Isotropy in [13]^C
Hyperfine Coupling in K3C60." To be published in J. Phys. Soc.
Jpn.,
Vol. 65, No. 8. NTT Basic Research Laboratories, 3-1 Morinosato-
Wakamiya, Atsugi-shi, Kanagawa 243-01, JAPAN. Key words:
superconducting fulleride, K3C60, [13]^C NMR, powder pattern,
knight
shift, hyperfine coupling, anisotropy, p-pi-orbitals.
H. Sasakura and K. Yoshida, "Superconductivity in the
Th-Contained
Cuprate of (Bi2-yPby)Sr2(Eu2-xThx)Cu2Oz." To be published in Physica
C
(in press). Department of Physics, Hamamatsu University School of
Medicine, Handa-cho, Hamamatsu, Shizuoka 431-31, JAPAN. Key words:
Th-
contained cuprate, 2222 phase, superconductivity, electrical
resistivity, magnetic susceptibility.
H. Sato and M. Naito, "Increase in the Superconducting Transition
Temperature by Anisotropic Strain Effect in (001) La1.85Sr0.15CuO4
Thin
Films on LaSrAlO4 Substrates." To be published in Physica C.
Material
Science Research Laboratory, NTT Basic Research Laboratories, 3-1
Morinosato Wakamiya, Atsugi-shi, Kanagawa 243-01, JAPAN; telephone
+81
462 40 3532; telefax +81 462 40 4724; e-mail
hisashi@will.brl.ntt.jp.
Key words: La2-xSrxCuO4, thin films, strain effect,
superconducting
transition temperature.
A. Sattar, J. P. Srivastava, S. V. Sharma, and T. K. Nath, "Effect
of
Er-Substitution on Superconducting and Metal-Insulator Transitions
in
2212 Bismuth Cuprate." To be published in Physica C (in press).
Contact J. P. Srivastava, Department of Physics, Aligarh Muslim
University, Aligarh 202
002, INDIA.
R. Scharnweber and M. Schilling, "Integrated YBa2Cu3O7 Magnetometer
with
Flux Transformer and Multiloop Pick-Up Coil." To be published in
Appl.
Phys. Lett. (Aug. 26, 1996). Institut fuer Angewandte Physik und
Zentrum fuer Mikrostrukturforschung, Universitaet Hamburg,
Jungiusstrasse 11, D-20355 Hamburg, GERMANY. 74.50.+r; 74.72.Bk;
74.76.Bz; 85.25.Dq.
P. Schaetzle, W. Bieger, U. Wiesner, P. Verges, and G. Krabbes,
"Melt
Processing of (Nd/Y)BaCuO and (Sm/Y)BaCuO Composites." To be
published
in Supercond. Sci. & Technol. Institut fuer Festkoerper- und
Werkstofforschung e.V., Postfach 270016, D-1171 Dresden, GERMANY;
e-mail
schaetzle@ifw-dresden.de.
A. Schilling, R. A. Fisher, N. E. Phillips, U. Welp, D. Dasgupta, W.
K.
Kwok, and G. W. Crabtree, "Calorimetric Measurement of a Latent Heat
at
the Vortex Lattice Melting Line of Untwinned YBa2Cu3O7." To be
published in Nature. Lawrence Berkeley Laboratory and Department
of
Chemistry, University of California, Berkeley, CA 94720.
M. Schilling, D. Reimer, R. Scharnweber, K. O. Subke, and U.
Merkt,
"Integrierte Magnetometer aus YBa2Cu3O7 fuer den Betrieb in
Unabgeschirmter Umgebung." Submitted to BMBF, Cologne, Germany,
June
1996. Institut fuer Angewandte Physik und Zentrum fuer
Mikrostrukturforschung, Universitaet Hamburg, Jungiusstrasse 11,
D-20355
Hamburg, GERMANY. Preprint in German.
H. G. Schnack, R. Griessen, P. Noordeloos, and K. Heeck,
"Continuously
Rotatable High Field Capacitance Torque Magnetometer." To be
published
in Physica C (in press). Faculty of Physics and Astronomy, Vrije
Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, THE
NETHERLANDS.
P. Schneider, G. Linker, R. Schneider, J. Reiner, and J. Geerk,
"The
Effect of Y and Ba Content on the Properties of YBaCuO Thin Films."
To
be published in Physica C (in press). Forschungszentrum
Karlsruhe,
Institut fuer Nukleare Festkoerperphysik, Postfach 3640, D-76021
Karlsruhe, GERMANY.
Mikhail A. Skvortsov, "Quantum and Thermal Depinning of a String from
a
Linear Defect." Preprint #ETH-TH/96-13. L. D. Landau Institute
for
Theoretical Physics, Moscow 117940, RUSSIA.
E. B. Sonin, "The Magnus Force in Superfluids and Superconductors."
Low
Temperature Laboratory, Helsinki University of Technology, 02150
Espoo,
FINLAND; e-mail esonin@boojum.hut.fi; preprint also available at
cond-
mat@xxx.lanl.gov (#9606099).
G. Stephens, "Anomalous Critical Current Enhancement in
Superconducting
Thin Films of a-Molybdenum Silicon." To be published in Physica C
(in
press). Department of Materials Science and Metallurgy, Cambridge
University, Cambridge, UNITED KINGDOM; telefax +44 1223 334 567.
G. K. Strukova, I. S. Smirnova, A. V. Bazhenov, S. A. Shevchenko, A.
I.
Kolyubakin, R. A. Dilanian, and V. Sh. Shekhtman, "A Cubic Phase
in
Ceramic Y-Ba-Cu-O Doped with Nb." To be published in Physica C
(in
press). Contact R. A. Dilanian, Institute of Solid State Physics,
Russian Academy of Sciences, Chernogolovka, Moscow 142432,
RUSSIA;
telefax +7 96 576 4111; e-mail ruben@issp.ac.ru.
M. D. Sumption, E. W. Collings, N. V. Vo, and S. X. Dou, "Eddy
Current
and Creep-Based Losses in CTFF-Type Bi:2223/Ag Multifilamentary
Tapes."
Presented at the 16th Int. Cryogenic Eng. Conf. and the Int.
Cryogenic
Mater. Conf. (ICEC/ICMC), Kitakyushu, Japan, May 20-24, 1996.
Applied
Superconductivity and Magnetism Laboratories, Department of
Materials
Science and Engineering, Ohio State University, 477 Watts Hall,
2041
College Road, Columbus, OH 43210-1178; telephone (614) 688-3684;
telefax
(614) 688-3677; e-mail mdsumption+@osu.edu.
C. S. Unnikrishnan, "Does a Superconductor Shield Gravity?" To be
published in Physica C (in press). Gravitation Experiments Group,
Tata
Institute of Fundamental Research, Homi Bhabha Road, Bombay 400
005,
INDIA; e-mail unni@tifrvax.tifr.res.in. Key words:
superconductivity,
Meissner effect, levitation, gravitational shielding.
I. Van Driessche, R. Mouton, and S. Hoste, "Rapid Formation of the
Bi2-
xPbxSr2Ca2Cu3Oy High Tc-Phase, Using Spray-Dried Nitrate
Precursor
Powders." To be published in Mater. Res. Bull. Department of
Inorganic
and Physical Chemistry, Division of Superconducting Materials,
Ghent
University, Krijgslaan 281, B-9000 Ghent, BELGIUM; telephone +32 9
264
44 40; telefax +32 9 264 49 83; e-mail
isabel.vandriessche@rug.ac.be.
Key words: ceramics, chemical synthesis, thermogravimetric analysis,
x-
ray diffraction, superconductivity.
I. Van Driessche, F. Persyn, L. Fiermans, and S. Hoste, "A
Statistical
Plackett-Burman Design of the Thermal Process in the Synthesis of
the
Bi-2223 HTSC." To be published in Supercond. Sci. & Technol.
Department of Inorganic and Physical Chemistry, Division of
Superconducting Materials, Ghent University, Krijgslaan 281,
B-9000
Ghent, BELGIUM; telephone +32 9 264 44 40; telefax +32 9 264 49 83;
e-
mail isabel.vandriessche@rug.ac.be. Key words: synthesis of
ceramic
superconductors, Placket-Burman design, electrical resistivity,
magnetic
susceptibility, XRD.
G. Villard, D. Pelloquin, A. Maignan, and A. Wahl, "Evidence of
Enhanced
Pinning Properties in Optimally Doped Bi2Sr2Ca1-xYxCu2O8+d Single
Crystals." To be published in Appl. Phys. Lett. Laboratoire
CRISMAT,
ISMRA et Universite de Caen, URA 1318, Bd. du Marechal Juin,
F-14050
Caen Cedex, FRANCE; telephone +33 16 31 45 29 16; telefax +33 16 31
95
16 00; e-mail physol@crismat.ismra.fr. 61.16.Di; 74.30.Ci;
74.60.Jg;
74.70.Vy; 81.10.Fq.
F. J. Villegas, D. R. Jackson, and J. T. Williams, "Leakage Fields
from
Planar Semi-Infinite Transmission Lines." Preprint #96:076;
submitted
to the Proc. of the IEEE MTT Int. Microwave Symp., San Francisco,
California, June 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.
T. B. Waje, I. K. Gopalakrishnan, R. Ganguly, and J. V. Yakhmi,
"Effect
of Ca Doping on the Structural and Superconducting Properties of
EuBaSrCu3O7-d." Submitted to J. Low Temp. Phys.: Proc. of the
Int.
Conf. on Phys. and Chem. of Molecular and Oxide Supercond.
(MOS'96),
Karlsruhe, Germany, Aug. 2-6, 1996. Computer Division, Bhabha
Atomic
Research Centre, Bombay 400 085, INDIA. 74.62.Bf; 74.62.Dh;
74.62.Fj;
76.60.
K. Watanabe, S. Awaji, J. Sakuraba, K. Watazawa, T. Hasebe, K.
Jikihara,
Y. Yamada, and M. Ishihara, "11 T Liquid Helium-Free
Superconducting
Magnet." To be published in Cryogenics. Institute for Materials
Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai
980-77,
JAPAN; telephone +81 22 215 2147; telefax +81 22 215 2149. Key
words:
high-temperature-superconducting current lead, GM cryocooler,
superconducting magnet, high field.
J. G. Wen, S. Mahajan, T. Morishita, and N. Koshizuka, "Full Coverage
of
Ultra-Thin SrTiO3 Layer in a-YBa2Cu3O7-x/SrTiO3/a-YBa2Cu3O7-x
Sandwiched
Thin Film." To be published in Physica C (in press).
Superconductivity
Research Laboratory, International Superconductivity Technology
Center
(ISTEC), 10-13 Shinonome 1-chrome, Koto-ku, Tokyo 135, JAPAN;
telephone
+81 3 3536-5703 through -5705; telefax +81 3 3536-5714 or -5717.
Rinke J. Wijngaarden, R. Griessen, J. Fendrich, and W.-K. Kwok,
"Influence of Twin-Planes in YBa2Cu3O7 on Magnetic Flux Movement
and
Current Flow." Submitted to Phys. Rev. B. Department of Physics
and
Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam,
THE
NETHERLANDS. Key words: twin planes, critical currents,
YBa2Cu3O7,
flux penetration.
Rinke J. Wijngaarden, H.J.W. Spoelder, R. Surdeanu, and R.
Griessen,
"Determination of 2D Current Patterns in Flat Superconductors
from
Magneto-Optical Measurements: An Efficient Inversion Scheme." To
be
published in Phys. Rev. B. Institute COMPAS and Department of
Physics
and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV
Amsterdam,
THE NETHERLANDS. Key words: high-Tc superconductivity,
magneto-optics.
J. T. Williams, J. D. Morrow, D. R. Jackson, and S. A. Long,
"Superconducting Microstrip Antennas." Preprint #96:078; to be
published in Advances in Microstrip and Printed Antennas, edited by
K.
F. Lee (John Wiley, 1997). 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.
A. Wisniewski, C. Czurda, H. W. Weber, M. Baran, M. Reissner, W.
Steiner, P. X. Zhang, and L. Zhou, "Influence of Oxygen Deficiency
and
of Neutron-Induced Defects on Flux Pinning in Melt Textured Bulk
YBa2Cu3O7-x Samples." To be published in Physica C (in press).
Institute of Physics, Polish Academy of Sciences, PL-02668
Warsaw,
POLAND; telefax +48 22 43 09 26; e-mail wisni@ifpan.edu.pl.
N. J. Wu, H. Lin, A. R. Zomorrodian, D. Liu, and A. Ignatiev,
"High
Temperature Retention Properties of Ferroelectric PZT/YBCO
Heterostructures Investigated by Pyroelectric Current and Phase
Detection." Preprint #96:079; submitted to the Proc. of the 1996
IEEE
Int. Symp. on the Applications of Ferroelectrics, East Brunswick,
New
Jersey, Aug. 18-21, 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.
X. S. Wu, S. S. Jiang, N. Xu, F. M. Pan, X. R. Huang, W. Ji, MAO
Zhiqiang, XU Gaoji, and ZHANG Yuheng, "Structure of
La1.85Sr0.15CuO4
Doped with Zn in High Doping Level." To be published in Physica C
(in
press). National Laboratory of Solid State Microstructures, Center
for
Advanced Studies in Science and Technology of Microstructures,
Nanjing
University, Nanjing 210093, PEOPLE'S REPUBLIC OF CHINA.
H. Yamauchi and M. Karppinen, "Structural Classification of
Superconducting Cuprates." To be published in Superlattices and
Microstructures. Materials and Structures Laboratory, Tokyo
Institute
of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226, JAPAN;
telephone
+81 45 924 5315; telefax +81 45 921 6953; e-mail
yamauchi@materia.titech.ac.jp.
S. L. Yan, L. Fang, M. S. Si, J. Wang, H. L. Cao, G. Samadi
Hosseinali,
and H. W. Weber, "Preparation and Properties of Tl-Based
Superconducting
Thin Films." Presented at the Eighth Int. Workshop on Critical
Currents
in Supercond., (8th IWCC), Kitakyushu, Japan, May 27-29, 1996.
Department of Electronics, Nankai University, Tianjin 300071,
PEOPLE'S
REPUBLIC OF CHINA; e-mail slyan@linux.nankai.edu.cn.
U. Yaron, P. L. Gammel, A. P. Ramirez, D. A. Huse, G. D'Anna, E.
Bucher,
A. M. Chang, R. Ruel, L. Pfeiffer, D. J. Bishop, K. Mortensen, and M.
R.
Eskildsen, "Structural Disordering of the Superconducting Flux
Lattice
Through the Peak Effect in Niobium." Submitted to Science. Lucent
Technologies, Bell Labs, Room 1D 217, 600 Mountain Avenue, P.O. Box
636,
Murray Hill, NJ 07974-0636; telephone (908) 582-4672; telefax (908)
582-
3260.
Jaimoo Yoo, Hyungsik Chung, Jaewoong Ko, Haidoo Kim, and Jian
Sha,
"Fabrication of Superconducting Joints Between PIT Processed
Bi-2223/Ag
Tapes by Single and Multiple Press and Reaction Annealing." To be
published in Physica C (in press). Korea Institute of Machinery
and
Materials, 66 Sangnam-dong, Changwon, Kyungnam, SOUTH KOREA; telefax
+82
551 80 3599.
X. Zhang, S. Y. Xu, W. H. Lu, C. K. Ong, S. C. Parker, and G. W.
Watson,
"Pressure-Induced Structural Changes in HgBa2CaCu2O6+d." To be
published in Physica C, Vol. 265 (in press). Department of
Physics,
National University of Singapore, Low Kent Ridge Road, Singapore
0511,
REPUBLIC OF SINGAPORE; telefax +65 777 6126.
COMING EVENTS
(An * indicates a previously listed event.)
Aug. 19 - 22, 1996: Strongly Correlated Electron Systems (SCES
'96),
Zurich, Switzerland. Main topics: heavy-electron phenomena, Kondo
and
electron-hybridization effects, magnetic correlations,
non-Fermi-liquid
behavior, correlations in novel superconductors, heavy electrons,
organics, cuprates, fullerenes, low-dimensional systems, and charge-
and
spin-fluctuation effects.
Contributions will be published in a special issue of Physica B.
For
further information, contact Nicole Osterwalder, Solid State
Physics
Laboratory ETH Zurich CH-8093 Zurich, Switzerland; telephone +41
1-633-
2335; telefax +41 1-633-1072.
May 12 - 14, 1997: 2nd SIAM Conference on Mathematical Aspects of
Materials Science, Holiday Inn Select, Philadelphia, PA.
Conference
will gather the interdisciplinary community of scientists working
on
mathematical and computational aspects of materials science.
Conference
will examine recent methodological advances in areas such as analysis
of
moving interfaces, fast boundary integral methods, macroscopic
consequences of microstructure, and pattern formation due to
energy
minimization. Will also highlight recent accomplishments in areas
such
as materials design, synthesis and processing, simulation of
phase-
transformation dynamics, and stress effects in thin films, and
identify
promising directions for new developments of a mathematical or
computational nature in areas such as atomic-scale modeling,
liquid
crystals and polymers, magnetic materials, and plasticity. Will
include
scientists from a broad range of backgrounds, including
mechanics,
physics, engineering, mathematics, and computational science.
Invited
presentations include Vortex Physics in Superconductors and Non-
Hermitian Localization by David Nelson (Harvard). Minisymposia
also
planned on superconductivity. Deadline for submission of
minisymposium
proposals, Sept. 16, 1996; contributed abstract deadline, Oct. 15,
1996.
For further information, contact SIAM, 3600 University City
Science
Center, Philadelphia, PA 19103-2688; telephone (215) 382-9800;
telefax
(215) 386-7999; e-mail meetings@siam.org or
http://www.siam.org/conf.htm.
June 30 - July 3, 1997: 3rd European Conference on Applied
Superconductivity (EUCAS'97), Veldhoven, The Netherlands. Objective
is
to provide an up-to-date and comprehensive overview of research
and
development activities in applications of all classes of
superconductors. Conference aims to encourage new cooperations on
European and wider international levels. Will include 4 plenary
sessions, 21 oral sessions, and 4 poster sessions with keynote
lecture
at the beginning of each oral session. One plenary session will
be
devoted to industrial applicability of superconductivity and
industrial
perspective. Program will be broadly divided into small-scale
&
electronic applications, and large-scale & power applications.
Former
category will include Josephson junctions, SQUIDs, digital
applications,
mixers/detectors, passive devices, oscillators, materials aspects
related to superconducting electronics, system aspects, and other
applications. Latter category will include fusion and SMES,
detectors
and accelerators; motors, generators, high magnetic fields, power
applications, materials aspects related to large-scale
applications,
system aspects, and other applications. For general conference
information, contact Convention Bureau Basics, P.O. Box 217, 7500
AE,
Enschede, The Netherlands; telephone +31 53-4894444; telefax +31
53-
4894442; e-mail a.spierenburg@basics.utwente.nl. For scientific
queries, contact eucas@tn.utwente.nl. Information also available at
the
web site
http://eucas.tn.utwente.nl/eucas/intro.htm.
RESOURCES
Information
Brochure from DOE: Superconductivity for Electric Systems Program
Plan
explains the collaborative work being done by electric utilities,
government, and industry to bring HTS technologies to the
marketplace.
Explains superconductivity and recent advances and discusses the
Superconductivity Partnership Initiative, current technology status,
and
Program plans and goals through the year 2000. For complimentary
copy
of the brochure, call Energetics at (301) 621-8432.
FYI
(High-Tc Update takes no responsibility for want ads listed in
this
section.)
The Superconductivity Technology Center at Los Alamos National
Laboratory is seeking postdoctoral candidates who can strongly
participate in multidisciplinary projects involving development
of
electronic devices based on high-temperature superconducting thin
films
and advanced oxides (such as ferroelectric and conductive
oxides).
Position demands experience/skills in thin-film deposition,
device
fabrication, and electrical and structural characterization of
thin
films and devices. A Ph.D. in electrical engineering, materials
science, or physics completed within the last three years (or soon to
be
completed) is required. Applicants should send a resume including
a
list of publications to Dean E. Peterson, Superconductivity
Technology
Center, Mail Stop K763, Los Alamos National Laboratory, Los Alamos,
NM
87545.
Fig. 1. Levitation of a person using the repulsive force between
melt-
powder-melt-growth (MPMG) processed YBa2Cu3O7-d pellets and
Fe-Nd-B
magnets mounted in the levitating disk. Pictured is I. Asakawa,
the
secretary for M. Murakami (SRL-ISTEC). (This picture will appear in
the
review article by M. Murakami et al. included in the preprint
list.)
High-Tc Update is the high-Tc superconductivity information
exchange
newsletter. Please send 1) preprints, reprints, and other
research
reports; 2) descriptions of on-going work; 3) meeting announcements
and
summaries.
The information contained herein is intended for limited
distribution.
Readers are expected to respect the rights of the authors.
Please address all contributions and inquiries to:
Dr. Sreeparna Mitra, A219 Physics, Ames Laboratory/Iowa State
University, Ames, Iowa 50011-3020. Telephone: (515) 294-3877.
Telefax:
(515) 294-1134. Telex: 269266. E-mail: MITRA@AMESLAB.GOV or
MITRA@IASTATE.EDU.
Project Director/Editor: Sreeparna Mitra
Science Editor: John R. Clem
High-Tc Update, Vol. 10, #15, August 1, 1996.