Path-Dependent Supercooling of the $^3$He Superfluid A-B transition

Dmytro Lotnyk; Anna Eyal; Nikolay Zhelev; Abhilash Sebastian; Yefan Tian; Aldo Chavez; Eric Smith; John Saunders; Erich Mueller; Jeevak Parpia

doi:10.1103/physrevlett.126.215301

arXiv · 2012.14044

Path-Dependent Supercooling of the $^3$He Superfluid A-B transition

Dmytro Lotnyk·Anna Eyal·Nikolay Zhelev·Abhilash Sebastian·Yefan Tian·Aldo Chavez·Eric Smith·John Saunders·Erich Mueller·Jeevak Parpia

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Abstract

We examine the discontinuous first-order superfluid $^3$He A to B transition in the vicinity of the polycritical point (2.232 mK and 21.22 bar). We find path-dependent transitions: cooling at fixed pressure yields a well defined transition line in the temperature-pressure plane, but this line can be reliably crossed by depressurizing at nearly constant temperature after transiting $T_{\rm c}$ at a higher pressure. This path dependence is not consistent with any of the standard B-phase nucleation mechanisms in the literature. This symmetry breaking transition is a potential simulator for first order transitions in the early universe.

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Dmytro Lotnyk, Anna Eyal, Nikolay Zhelev, Abhilash Sebastian, Yefan Tian, Aldo Chavez, Eric Smith, John Saunders, Erich Mueller, Jeevak Parpia. 2020-12-28. Path-Dependent Supercooling of the $^3$He Superfluid A-B transition. https://doi.org/10.1103/physrevlett.126.215301

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