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arXiv · 1805.06493

Flavor Symmetry and Ferroelectric Nematics in Transition Metal Dichalcogenides

Patrick Cheung·Zhi-qiang Bao·Fan Zhang
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Abstract

Recent magneto-transport experiments have provided compelling evidence for the presence of an energetically isolated threefold Q-valley degeneracy in few-layer transition metal dichalcogenides. We study the flavor SU(3) symmetry breaking when each Landau level triplet is one-third filled or empty and predict that a pure flavor nematic phase and a flavorless charge-density-wave phase will occur respectively below and above a critical magnetic field. Surprisingly, electrons carry flavor-dependent electric dipole moments even at zero magnetic field, rendering the nematics ferroelectric, allowing electric-field manipulation of the flavors, and leading to the concept of flavortronics.

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Patrick Cheung, Zhi-qiang Bao, Fan Zhang. 2018-05-16. Flavor Symmetry and Ferroelectric Nematics in Transition Metal Dichalcogenides. https://arxiv.org/abs/1805.06493

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