Morphological false-vacuum decay in dipolar supersolids

TL;DR

This paper investigates false-vacuum decay between different supersolid phases in a dipolar gas, using numerical simulations to analyze bubble nucleation, growth, and decay rates, highlighting the platform's experimental accessibility.

Contribution

It introduces a novel study of false-vacuum decay in dipolar supersolids, combining numerical analysis with a minimal effective model, and emphasizes real-space bubble formation observable via in situ imaging.

Findings

Bubble growth speed is limited by the slowest sound mode in the supersolid.

Numerical decay rates match predictions from the Coleman bounce model.

Real-space density imaging can directly observe bubble formation.

Abstract

False-vacuum decay between two morphologically distinct supersolid phases via bubble nucleation is studied in a uniform dipolar gas confined to the plane. Starting from a metastable honeycomb state, the formation of stripe phase domains is simulated numerically by means of a stochastic projected extended Gross-Pitaevskii equation. The speed of bubble growth is analyzed in relation to the multiple speeds of sound of the supersolid, and is found to be set by the slowest of these sounds. The vacuum decay rate is numerically extracted and compared against a minimal effective model for the Coleman bounce solution connecting the two supersolid orders. Our results establish dipolar supersolids as a novel and versatile platform for studying false-vacuum decay. This setting offers a rich structure of metastable states and collective excitations that come into play in the decay. Furthermore, here, in contrast to previous studies, bubble formation occurs directly in the real-space density and can be probed with \textit{in situ} imaging.