AC Josephson effect in the long voltage-biased SINIS junction

TL;DR

This paper develops a theoretical framework for understanding the AC Josephson effect in long SINIS junctions with strong normal scattering, providing analytical expressions for current oscillations and their temperature dependence.

Contribution

It introduces a new analytical model for non-stationary coherent effects in superconductor-normal-superconductor structures with strong interface scattering.

Findings

Derived analytical expressions for time-dependent Green functions.

Identified the dominance of the second-harmonic Josephson current at high temperatures.

Calculated non-stationary corrections to the distribution function in high-temperature limit.

Abstract

Theory of non-stationary coherent effects is developed for superconductor-normal-superconductor (SNS) structures with relatively strong normal scattering on S/N interfaces (interface resistance is large compared to intrinsic resistance of N metal). Analitical expressions are found for the time-dependent anomalous Green functions induced in the N region under the fixed-voltage-bias. The amplitude of the current oscillations is determined in non-equilibrium conditions. Non-stationary correction to the distribution function is calculated in high-temperature limit and found to be slowly decreasing with the temperature, leading to the dominance of the second-harmonic term in the Josepshon current at high temperatures and low voltage.