Exploring quantum phase slips in 1D bosonic systems

TL;DR

This paper experimentally investigates quantum phase slips in one-dimensional ultracold bosonic superfluids, demonstrating control over the crossover from thermal to quantum phase slips and addressing related phenomena like superfluid breakdown and Mott insulator formation.

Contribution

It provides the first experimental exploration of quantum phase slips in ultracold quantum gases and demonstrates control over their crossover regime.

Findings

Observation of signatures of quantum phase slips in ultracold gases

Control over the crossover from thermal to quantum phase slips

Insights into superfluid breakdown and Mott insulator emergence

Abstract

Quantum phase slips, i.e the primary excitations in one-dimensional superfluids at low temperature, have been well characterized in most condensed-matter systems, with the notable exception of ultracold quantum gases. Here we present our experimental investigation of the dissipation in onedimensional Bose superfluids flowing along a periodic potential, which show signatures of the presence of quantum phase slips. In particular, by controlling the velocity of the superfluid and the interaction between the bosons we are apparently able to drive a crossover from a regime of thermal phase slips into a regime of quantum phase slips. Achieving a good control of quantum phase slips in ultracold quantum gases requires to keep under control other phenomena such as the breaking of superfluidity at the critical velocity or the appearance of a Mott insulator in the strongly correlated regime. Here we show our current results in these directions.