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Random-Matrix Theory: Distribution of Mesoscopic Supercurrents through a Chaotic Cavity

M. Garst·T. Kopp
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Abstract

We investigate the distribution of the supercurrent through a chaotic quantum dot which is strongly coupled to two superconductors when the Thouless energy is large compared to the superconducting energy gap. The distribution function of the critical currents P(I_c) is known to be Gaussian in the limit of large channel number N. For N=1, we present an analytical low-temperature expression for this distribution function, valid both in the presence and in the absence of time-reversal symmetry. It connects directly the distribution of transmission coefficients to the distribution of critical currents. The case of arbitrary channel number (N>1) is discussed numerically, and for small critical currents analytically.

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M. Garst, T. Kopp. 2001-09-27. Random-Matrix Theory: Distribution of Mesoscopic Supercurrents through a Chaotic Cavity. https://arxiv.org/abs/cond-mat/0109520

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