Cooperative orbital moments and edge magnetoresistance in monolayer WTe${}_2$

Abstract

We argue that edge electrons in monolayer WTe${}_2$ can possess a "cooperative" orbital moment (COM) that critically impacts its edge magnetoresistance behavior. Arising from the cooperative action of both Rashba and Ising spin orbit coupling, COM quickly achieves large magnitudes (of order few Bohr magnetons) even for relatively small spin-orbit coupling strengths. As we explain, such large COM magnitudes arise from an unconventional cooperative spin canting of edge spins when Rashba and Ising spin orbit coupling act together. Strikingly, COM can compete with spin moments to produce an unusual anisotropic edge magnetoresistance oriented at an oblique angle. In particular, this competition produces a direction along which $\mathbf{B}$ is ineffective at gapping out the edge spectrum leaving it nearly gapless. As a result, large contrasts in gap sizes manifest as $\mathbf{B}$ is rotated granting giant anisotropic magnetoresistance of 0.1-10 million % at 10 T and low temperature.

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Cited by in corpus (7)

• Determination of the spin axis in quantum spin Hall insulator monolayer WTe2
• Determination of the spin orientation of helical electrons in monolayer WTe2
• Non-linear ballistic response of quantum spin-Hall edge states
• Quantum spin Hall edge states and interlayer coupling in twisted-bilayer WTe${}_2$
• Theory of Glide Symmetry Protected Helical Edge States in WTe${}_2$ Monolayer
• Edge spin transport in the disordered two-dimensional topological insulator WTe${}_2$
• Inverse Ising effect and Ising magnetoresistance