Journal article
Strong nonequilibrium coherent states in mesoscopic superconductor-semiconductor-superconductor junctions
A biased superconductor-normal metal-superconductor junction is known to be a strong nonequilibrium system, where Andreev scattering at the interfaces creates a quasiparticle distribution function far from equilibrium, a manifestation of this is the well-known subgap structure in the I/V characteristic, with peaks in the conductance at V = 2 Delta/ne.
We study an SNS structure consisting of highly doped diffusive GaAs with superconducting electrodes of aluminum with one Electrode configured as a flux-sensitive interferometer. This enables us to probe the coherent nature of the quasiparticle states at subgap bias voltage. Oscillations in the conductance as a function of flux are seen at zero bias voltage and disappear below experimental resolution as the bias voltage exceeds the Thouless energy E-t = (h) over bar D/L-2, where L is the junction length.
The oscillations reappear at higher bias in a region around the superconducting energy gap V = Delta/e corresponding to the subgap conductance peak n = 2.
Language: | English |
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Publisher: | Kluwer Academic Publishers-Plenum Publishers |
Year: | 1999 |
Pages: | 839-842 |
Proceedings: | International workshop on Macroscopic Quantum Tunneling and Coherence |
ISSN: | 15571947 , 15571939 , 08961107 and 15729605 |
Types: | Journal article |
DOI: | 10.1023/A:1007757715089 |
ORCIDs: | 0000-0001-6149-281X , Taboryski, Rafael Jozef and Hansen, Jørn Bindslev |