Transport in a One-Dimensional Superfluid: Quantum Nucleation of Phase Slips

TL;DR

This paper derives an analytical expression for the quantum decay rate of superflow in a 1D Bose-Einstein condensate with a weak link, revealing how fluctuations influence phase slip nucleation and remove expected phase transitions.

Contribution

It provides a novel analytical derivation of the quantum decay rate considering damping and fluctuations, clarifying the impact on phase slip dynamics in 1D superfluids.

Findings

Algebraic flow-pressure relation for quantum phase slips

Short-wavelength fluctuations remove the quantum phase transition

Effective action resembles a damped massive particle in a periodic potential

Abstract

We present an analytical derivation for the quantum decay rate of the superflow through a weak link in a one-dimensional Bose-Einstein-condensate. The effective action for the phase difference across the link reduces to that of a massive particle with damping subject to a periodic potential. We find an algebraic flow-pressure relation, characteristic for quantum nucleation of phase slips in the link and show how short-wave length fluctuations renormalizing the interaction between the Bosons remove the quantum phase transition expected in this class of systems.