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arXiv · 1901.04130

High-pressure lithium as an elemental topological semimetal

S. F. Elatresh·Zhimou Zhou·N. W. Ashcroft·S. A. Bonev·Ji Feng·Roald Hoffmann
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Abstract

Topological semimetals generally contain heavy elements. Using density-functional theoretic calculations, we predict that three dense lithium polymorphs in the pressure range 200--360 GPa display nontrivial semimetallic electronic structure. Specifically, these high-pressure phases exhibit Fermi pockets which are degenerate over a loop in $\boldsymbol{k}$-space, around which an encircling $\bm k$-space path is threaded by $\pm \pi$ Berry phase. Accordingly, these dense lithium phases are topological nodal loop semimetals involving a single light element.

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S. F. Elatresh, Zhimou Zhou, N. W. Ashcroft, S. A. Bonev, Ji Feng, Roald Hoffmann. 2019-01-14. High-pressure lithium as an elemental topological semimetal. https://doi.org/10.1103/physrevmaterials.3.044203

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