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arXiv · 1604.08225

Topological surface states in dense solid hydrogen

Ivan I. Naumov·Russell J. Hemley
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Abstract

It has recently been established that two-dimensional massless graphene-like systems and three-dimensional line-node topological semimetals comprise a special class of centrosymmetric materials where edge/surface states of topological nature inevitably appear in some k-regions. We show that the phases of solid hydrogen produced at megabar pressures can be line-node topological semimetals. In such phases, the material exhibits topological surface states and therefore can be a poor bulk metal but good surface conductor. The results may help to explain discrepant high-pressure experimental data reported for dense hydrogen as well as provide predictions for future measurements, including possible surface superconductivity in hydrogen. Related topological behavior may be expected in high-pressure phases formed in other elements including simple metals.

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Ivan I. Naumov, Russell J. Hemley. 2016-04-27. Topological surface states in dense solid hydrogen. https://doi.org/10.1103/physrevlett.117.206403

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