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arXiv · 1803.04021

A highly asymmetric nodal semimetal in bulk SmB6

N. Harrison
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Abstract

We show that novel low temperature properties of bulk SmB6, including the sudden growth of the de Haas-van Alphen amplitude (and heat capacity) originating from the bulk at millikelvin temperatures and a previously unreported linear-in-temperature bulk electrical conductivity at liquid helium temperatures, signal the presence of a highly asymmetric nodal semimetal. We show how the highly asymmetric nodal semimetal can be the result of a topological transformation, of the type recently considered by Shen and Fu, occurring in a Kondo lattice with dispersionless f-electron levels and Sm vacancies or other lattice defects. If supported by further data experimental, the existence of a nodal semimetal would cast considerable doubt over a neutral Fermi surface being required to explain the origin of the dHvA effect SmB6.

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N. Harrison. 2018-03-11. A highly asymmetric nodal semimetal in bulk SmB6. https://doi.org/10.1103/physrevlett.121.026602

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