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arXiv · 2308.04116

Phase diagram of muonium hydride: when dimensionality matters

Jieru Hu·Massimo Boninsegni
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Abstract

We carry out a theoretical investigation of the low-temperature phase diagram of muonium hydride in two dimensions, using numerical simulations. It is shown that the phase diagram of this substance is qualitatively different in two and three dimensions. Specifically, while in three dimensions it has been shown to be essentially identical to that of parahydrogen, i.e., only displaying a single (crystalline) phase, in two dimensions it is very similar to that of He-4, with an equilibrium liquid phase that turns superfluid at a temperature as high as ~ 2.2 K, and that crystallizes under applied pressure. To our knowledge, this is the first well-described case of a condensed matter system whose phase diagram is drastically altered by dimensional reduction.

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Jieru Hu, Massimo Boninsegni. 2023-08-08. Phase diagram of muonium hydride: when dimensionality matters. https://doi.org/10.1088/1572-9494%2Fad1d50

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