Quantum stability and screening in superconducting metallic weak links

Journal Article · Sun Apr 01 00:00:00 EST 1984 · Phys. Rev. B: Condens. Matter; (United States)

OSTI ID:6810575

Kuemmel, R

Approximation methods are developed for solving the time-dependent Bogoliubov--de Gennes equations for inhomogeneous superconducting systems with electromagnetic fields and thermal fluctuations. Space and time variations of the pair potential's phase in weak links are transformed into the appropriate vector and scalar potentials which are handled perturbation theoretically. In this way we compute quasiparticle scattering in superconducting-normal-superconducting junctions due to the random voltage of Nyquist-Johnson noise and obtain a microscopic criterion for the destruction of phase coherence between the S layers. Considering the problem of size quantization of Andreev states bound in the N region, we show that, at sufficiently high temperatures, a great number of them survive the destruction of phase coherence by thermal fluctuations. The first step of an iteration process which uses the gauge-invariant phase difference in Bardeen and Johnson's Josephson current allows an estimate of the amount of screening of magnetic fields by Josephson currents.

• Research Organization: Physikalisches Institut der Universitaet Wuerzburg, D-8700 Wuerzburg, Federal Republic of Germany
• OSTI ID: 6810575
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Vol. 29:7
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
SUPERCONDUCTORS
QUASI PARTICLES
TEMPERATURE NOISE
BOGOLYUBOV METHOD
COHERENCE LENGTH
DISTURBANCES
ELECTROMAGNETIC FIELDS
EXCITATION
METALS
PERTURBATION THEORY
RESPONSE FUNCTIONS
SPATIAL DISTRIBUTION
SPECTRA
TIME DEPENDENCE
DIMENSIONS
DISTRIBUTION
ELEMENTS
ENERGY-LEVEL TRANSITIONS
FUNCTIONS
LENGTH
NOISE
656101* - Solid State Physics- Superconductivity- General Theory- (-1987)