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arXiv · 2001.05305

Stability and superconductivity of lanthanum and yttrium decahydrides

Alice M. Shipley·Michael J. Hutcheon·Mark S. Johnson·Chris J. Pickard·Richard J. Needs
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Abstract

Rare-earth hydrides can exhibit high-temperature superconductivity under high pressure. Here, we apply a crystal structure prediction method to the current record-holding $T_c$ material, LaH$_{10}$, and a candidate for even higher $T_c$, YH$_{10}$. We find a pressure-induced phase transition from the experimentally observed cubic LaH$_{10}$ phase to a new hexagonal phase at around 420 GPa. This hexagonal phase could explain experimental observations of hcp impurities in fcc samples. We find that YH$_{10}$ forms similar structures to LaH$_{10}$ and discuss the sensitivity of superconductivity calculations to the computational parameters used.

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Alice M. Shipley, Michael J. Hutcheon, Mark S. Johnson, Chris J. Pickard, Richard J. Needs. 2020-01-15. Stability and superconductivity of lanthanum and yttrium decahydrides. https://doi.org/10.1103/physrevb.101.224511

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