Cooper-pair current through ultrasmall Josephson junctions

Journal Article · Fri Jul 01 04:00:00 EDT 1994 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.50.395· OSTI ID:7041677

Ingold, G; Grabert, H ^[1]; Eberhardt, U ^[2]

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1. Fachbereich Physik, Universitaet Essen, D-45117 Essen (Germany)
2. Fachbereich Physik, Universitaet Duisburg, D-47048 Duisburg (Germany)

The current-voltage characteristics of ultrasmall Josephson junctions sensitively depend on the electromagnetic environment of the junction. When the charging energy exceeds the Josephson coupling energy, the usual supercurrent at zero voltage is completely suppressed. However, for typical environmental impedances, which are small compared to the resistance quantum, stochastic Cooper-pair tunneling leads to a supercurrent peak at a small finite voltage which is proportional to the temperature and the low-frequency resistance of the external circuit. An analytic expression for the form of this universal peak, which is independent of the high-frequency behavior of the environment, is given. With increasing Josephson coupling the peak merges into the usual supercurrent of a Josephson junction. At larger voltages the Cooper-pair current depends on details of the environment. Current peaks are shown to result from resonances in the environmental impedance. Specifically, the case of an [ital LC] transmission line of finite length is discussed.

• OSTI ID: 7041677
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 50:1; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665412* -- Superconducting Devices-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
COOPER PAIRS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
JOSEPHSON JUNCTIONS
JUNCTIONS
MIM JUNCTIONS
MINIATURIZATION
PHYSICAL PROPERTIES
SEMICONDUCTOR JUNCTIONS
SUPERCONDUCTING JUNCTIONS
TUNNEL EFFECT