1999/01/31 by T. Hoss, Christoph Strunk, C. Strunk +6 · 4 citations
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Superconducting and THz Device Technology #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevb.62.4079
published as Physical Review B, Vol. 62, p. 4079 (2000) · 7 pages, 7 figures, extended version
arxiv created 2000/02/24 · openalex publication_date 2000/08/01 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We have studied superconductor/normal-metal/superconductor (SNS) junctions consisting of short Au or Cu wires between Nb or Al banks. The Nb based junctions display inherent electron heating effects induced by the high thermal resistance of the NS boundaries. The Al based junctions show in addition subharmonic gap structures in the differential conductance dI/dV and a pronounced peak in the excess noise at very low voltages V. We suggest that the noise peak is caused by fluctuations of the supercurrent at the onset of Josephson coupling between the superconducting banks. At intermediate temperatures where the supercurrent is suppressed a noise contribution \ensuremath∝1/V remains, which suggests the presence of a long-range proximity effect in the noise.