On the probability of quantum phase slips in superconducting nanowires

TL;DR

This paper analyzes quantum phase slips in ultrathin superconducting nanowires, showing that decay rates are generally very low due to momentum conservation, but dissipation could enhance phase slip transitions under certain conditions.

Contribution

It provides a theoretical estimate of decay rates for quantum phase slips considering disorder and Ohmic losses, highlighting the potential role of dissipation in phase slip enhancement.

Findings

Decay rates from potential scattering are negligible.

Ohmic losses can increase decay rates under specific conditions.

Momentum conservation suppresses quantum phase slip probability.

Abstract

The paper discusses mechanisms for decay of supercurrents in ultrathin superconducting wires driven by quantum fluctuations. We argue that momentum conservation strongly suppresses probability of such decay and estimate the rates for two decay channels: potential scattering of condensate due to the disorder and attenuation of the plasmon mode due to the presence of normal component, i.e., Ohmic losses. We find that while both mechanisms yield non-zero decay rates, their values are too small to provide any substantial contribution to the resistivity of the wires. The rate associated with the latter mechanism, however, is much greater, and it is possible that under the appropriate conditions dissipation may lead to appreciable enhancement of quantum phase slip transitions.