Spontaneous breaking of time-reversal symmetry at the edges of 1T' monolayer transition metal dichalcogenides

Abstract

Using density functional theory calculations and the Greens's function formalism, we report the existence of magnetic edge states with a non-collinear spin texture present on different edges of the 1T' phase of the three monolayer transition metal dichalcogenides (TMDs): MoS${}_2$, MoTe${}_2$ and WTe${}_2$. The magnetic states are gapless and accompanied by a spontaneous breaking of the time-reversal symmetry. This may have an impact on the prospects of utilizing WTe${}_2$ as a quantum spin Hall insulator. It has previously been suggested that the topologically protected edge states of the 1T' TMDs could be switched off by applying a perpendicular electric field. We confirm with fully self-consistent DFT calculations, that the topological edge states can be switched off. The investigated magnetic edge states are seen to be robust and remains gapless when applying a field.

arXiv comment7 pages, 7 figures

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Cited by in corpus (5)

• Theory of Glide Symmetry Protected Helical Edge States in WTe${}_2$ Monolayer
• Temperature effects in topological insulators of transition metal dichalcogenide monolayers
• Spin polarization in Lateral two-dimensional Heterostructures
• Designing Extremely Low-Power Topological Transistors with 1T'-MoS2 and HZO for Cryogenic Applications
• First-principles modeling of electrostatics and transport in 2D topological transistors