Superfluidity and Swallowtails; Hysteretic Behavior in Bose Condensates

TL;DR

This paper develops a theoretical framework explaining hysteresis and swallowtail loops in Bose gases, linking them to superfluidity and analyzing decay rates of metastable states due to quantum effects.

Contribution

It provides a physical interpretation of swallowtail loops as signs of superfluidity and models hysteretic phenomena in Bose condensates.

Findings

Swallowtail loops indicate superfluidity and hysteresis in Bose gases.

Decay rates of metastable states are quantified considering quantum fluctuations.

The theory applies to Bose gases in rings and optical lattices.

Abstract

We present a theory of hysteretic phenomena in Bose gases, using superfluidity in one dimensional rings and in optical lattices as primary examples. Through this study we are able to give a physical interpretation of swallowtail loops recently found by many authors in the mean-field energy structure of trapped atomic gases. These loops are a generic sign of hysteresis, and in the present context are an indication of superfluidity. We have also calculated the rate of decay of metastable current carrying states due to quantum fluctuations.