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arXiv · 2108.05740

False vacuum decay in an ultracold spin-1 Bose gas

Thomas P. Billam·Kate Brown·Ian G. Moss
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Abstract

We propose an ultracold atom analogue of early universe vacuum decay using all three states of a spin-1 Bose gas. We consider a one-dimensional system with both radio frequency and optical Raman coupling between internal states. An advantage of our proposal is the lack of a time-modulated coupling, which can lead to instabilities. Within the elaborate phase structure of the system we identify an effective Klein-Gordon field and use Gross-Pitaevskii simulations within the truncated Wigner approximation to model the decay of its false vacuum. We examine the dependence of the rate of vacuum decay on particle density for $^{7}$Li and $^{41}$K and find reasonable agreement with instanton methods.

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Thomas P. Billam, Kate Brown, Ian G. Moss. 2021-08-12. False vacuum decay in an ultracold spin-1 Bose gas. https://doi.org/10.1103/physreva.105.l041301

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