Heating of quasiparticles driven by oscillations of the order parameter in short superconducting microbridges

TL;DR

This paper predicts a novel 'heating' effect of quasiparticles caused by order parameter oscillations in short superconducting microbridges, contrasting previous findings of quasiparticle cooling.

Contribution

It introduces the concept of quasiparticle heating driven by order parameter oscillations, considering finite relaxation times and spectral function dependencies, which was not addressed before.

Findings

Quasiparticles are heated by order parameter oscillations in the resistive state.

The effect is opposite to previous theories predicting quasiparticle cooling.

Finite relaxation time and spectral function dependence are key factors.

Abstract

We predict 'heating' of quasiparticles driven by order parameter oscillations in the resistive state of short superconducting microbridges. The finite relaxation time of the magnitude of the order parameter $|\Delta|$ and the dependence of the spectral functions both on $|\Delta|$ and the supervelocity $Q$ are the origin of this effect. Our result is opposite to those of Aslamazov and Larkin (Zh. Eks. Teor. Fiz. {\bf 70}, 1340 (1976)) and Schmid, Schon and Tinkham (Phys. Rev. B {\bf 21} 5076 (1980)) where 'cooling' of quasiparticles was found.