1,020 research outputs found
The Effects of d_{x^2-y^2}-d_{xy} Mixing on Vortex Structures and Magnetization
The structure of an isolated single vortex and the vortex lattice, and the
magnetization in a -wave superconductor are investigated within a
phenomenological Ginzburg-Landau (GL) model including the mixture of the
-wave and -wave symmetry. The isolated single vortex
structure in a week magnetic field is studied both numerically and
asymptotically. Near the upper critical field , the vortex lattice
structure and the magnetization are calculated analytically.Comment: 14 pages, REVTeX, 2 EPS figures, Journal of Physics: Condensed Matter
(in press
The Plant Stem: A Microscopic Aspect
Plant stem construction; Plant cell contents; Plant cell walls; Plant meristems; Anatomy of pteridophyta; Stem evolution; Plant ecology; Wood degradation; Fossilization; Plant morpholog
Tilt Grain-Boundary Effects in S- and D-Wave Superconductors
We calculate the s- and d-wave superconductor order parameter in the vicinity
of a tilt grain boundary. We do this self-consistently within the Bogoliubov de
Gennes equations, using a realistic microscopic model of the grain boundary. We
present the first self-consistent calculations of supercurrent flows in such
boundaries, obtaining the current-phase characteristics of grain boundaries in
both s-wave and d-wave superconductors
Research and education in management of large-scale technical programs
A research effort is reported which was conducted by NASA in conjunction with Drexel University, and which was aimed at an improved understanding of large scale systems technology and management
Phase-sensitive Evidence for d-wave Pairing Symmetry in Electron-doped Cuprate Superconductors
We present phase-sensitive evidence that the electron-doped cuprates
Nd1.85Ce0.15CuO4-y (NCCO) and Pr1.85Ce0.15CuO4-y (PCCO) have d-wave pairing
symmetry. This evidence was obtained by observing the half-flux quantum effect,
using a scanning SQUID microscope, in c-axis oriented films of NCCO or PCCO
epitaxially grown on tricrystal [100] SrTiO3 substrates designed to be
frustrated for a d(x2-y2) order parameter. Samples with two other
configurations, designed to b unfrustrated for a d-wave superconductor, do not
show the half-flux quantum effect.Comment: 4 pages, Latex, 4 figure
A Convergent Method for Calculating the Properties of Many Interacting Electrons
A method is presented for calculating binding energies and other properties
of extended interacting systems using the projected density of transitions
(PDoT) which is the probability distribution for transitions of different
energies induced by a given localized operator, the operator on which the
transitions are projected. It is shown that the transition contributing to the
PDoT at each energy is the one which disturbs the system least, and so, by
projecting on appropriate operators, the binding energies of equilibrium
electronic states and the energies of their elementary excitations can be
calculated. The PDoT may be expanded as a continued fraction by the recursion
method, and as in other cases the continued fraction converges exponentially
with the number of arithmetic operations, independent of the size of the
system, in contrast to other numerical methods for which the number of
operations increases with system size to maintain a given accuracy. These
properties are illustrated with a calculation of the binding energies and
zone-boundary spin- wave energies for an infinite spin-1/2 Heisenberg chain,
which is compared with analytic results for this system and extrapolations from
finite rings of spins.Comment: 30 pages, 4 figures, corrected pd
Extended Impurity Potential in a d_{x^2-y^2} Superconductor
We investigate the role of a finite potential range of a nonmagnetic impurity
for the local density of states in a d_{x^2-y^2} superconductor. Impurity
induced subgap resonances are modified by the appearance of further scattering
channels beyond the --wave scattering limit. The structure of the local
density of states (DOS) in the vicinity of the impurity is significantly
enhanced and therefore improves the possibility for observing the
characteristic anisotropic spatial modulation of the local DOS in a d_{x^2-y^2}
superconductor by scanning tunneling microscopy.Comment: 4 pages, Revtex, with 4 embedded eps figures. Submitted to Phys. Rev.
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