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arXiv · 1808.05981

Emergence of topologically protected states in MoTe$_{2}$ Weyl semimetal with layer stacking order

John A. Schneeloch·Chunruo Duan·Xiaoping Wang·Jun Liu·Junjie Yang·Despina Louca
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Abstract

Electronic tunability in crystals with weakly-bound layers can be achieved through layer stacking order. One such example is MoTe$_2$, where the low-temperature orthorhombic T$_d$ phase is topological and host to Weyl quasiparticles. The transition mechanism to the non-trivial topology is elucidated by single crystal neutron diffraction. Upon cooling from the monoclinic 1T$\prime$ to the T$_d$ phase, diffuse scattering accompanies the transition, arising from random, in-plane layer displacements, and dissipates upon entering the T$_d$ phase. Diffuse scattering is observed only in the H0L plane due to irreversible layer shifts along the c-axis that break the centrosymmetry of the monoclinic lattice.

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John A. Schneeloch, Chunruo Duan, Xiaoping Wang, Jun Liu, Junjie Yang, Despina Louca. 2019-02-15. Emergence of topologically protected states in MoTe$_{2}$ Weyl semimetal with layer stacking order. https://doi.org/10.1103/physrevb.99.161105

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