Bimodal distribution of delay times and splitting of the zero-bias conductance peak in a double-barrier normal-superconductor junction

C. W. J. Beenakker; V. A. Zakharov

doi:10.1103/hl4g-9frn

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arXiv · 2506.18515

Bimodal distribution of delay times and splitting of the zero-bias conductance peak in a double-barrier normal-superconductor junction

C. W. J. Beenakker·V. A. Zakharov

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Abstract

We formulate a scattering theory of the proximity effect in a weakly disordered SININ junction (S = superconductor, I = insulating barrier, N = normal metal). This allows to relate the conductance and density of states of the junction to the scattering times $\tau$ (eigenvalues of the Wigner-Smith time-delay matrix). The probability density $P(\tau)$ has two peaks, at a short time $\tau_{\rm min}$ and a late time $\tau_{\rm max}$. The density of states at the Fermi level is the geometric mean of the two times. The splitting of the zero-bias conductance peak is given by $\hbar/\tau_{\rm max}$.

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C. W. J. Beenakker, V. A. Zakharov. 2025-06-23. Bimodal distribution of delay times and splitting of the zero-bias conductance peak in a double-barrier normal-superconductor junction. https://doi.org/10.1103/hl4g-9frn

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