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arXiv · 1808.09585

Spin-orbit-stable type-II nodal line band crossing in n-doped monolayer MoX2 (X=S,Se,Te)

Kyung-Han Kim·Bohm Jung Yang·Hyun-Woo Lee
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Abstract

1H-phase monolayer transition-metal dichalcogenides have spin-split electronic band structures near the K(K') point due to strong spin-orbit coupling and intrinsic inversion symmetry breaking. In case of the monolayer MoX2 (X=S, Se, Te), the spin-split conduction bands cross near the K(K') point. We show that the band crossing occurs not only along the high symmetry directions, but also along arbitrary directions due to a mirror reflection symmetry of the monolayer. As a result, n-doped monolayer MoX2 is a two-dimensional type-II nodal-line material.

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Kyung-Han Kim, Bohm Jung Yang, Hyun-Woo Lee. 2018-12-12. Spin-orbit-stable type-II nodal line band crossing in n-doped monolayer MoX2 (X=S,Se,Te). https://doi.org/10.1103/physrevb.98.245422

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