Long-range coherence and mesoscopic transport in N-S metallic structures

• Main Authors: Courtois, H, Gandit, Ph, Pannetier, B, Mailly, D
• Format: Journal Article
• Language: English
• Published: 26.10.1998
• Subjects: Physics - Disordered Systems and Neural Networks; Physics - Materials Science; Physics - Mesoscale and Nanoscale Physics; Physics - Other Condensed Matter; Physics - Quantum Gases; Physics - Soft Condensed Matter; Physics - Statistical Mechanics; Physics - Strongly Correlated Electrons; Physics - Superconductivity
• DOI: 10.48550/arxiv.cond-mat/9810339

Superlattices and Microstructures 25, 721 (1999) We review the mesoscopic transport in a diffusive proximity superconductor made of a normal metal (N) in metallic contact with a superconductor (S). The Andreev reflection of electrons on the N-S interface is responsible for the diffusion of electron pairs in N. Superconducting-like properties are induced in the normal metal. In particular, the conductivity of the N metal is locally enhanced by the proximity effect. A re-entrance of the metallic conductance occurs when all the energies involved (e.g. temperature and voltage) are small. The relevant characteristic energy is the Thouless energy which is $\hbar$ divided by the diffusion time for an electron travelling throughout the sample. In loop-shaped devices, a 1/T temperature-dependent oscillation of the magnetoresistance arises with a large amplitude from the long-range coherence of low-energy pairs.