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arXiv · 1907.06605

Magnetic Effects on Topological Chiral Channels in Bilayer Graphene

Aaron Winn·John Maier·Andrew Jiao·Jeffrey C. Y. Teo
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Abstract

We study the effect of a magnetic field on topological chiral channels of bilayer graphene at electric domain walls. The persistence of chiral edge states is attributed to the difference in valley Chern number in the regions of opposite electric field. We explore the regime of large electric and magnetic fields perpendicular to the lattice. The magnetic field shifts the channel away from our electric interface in a way that is inconsistent with the semiclassical expectation from the Lorentz force. Moreover, the magnetic field causes an imbalanced layer occupation preference to the chiral channels. These behaviors admit analytic solutions in the limits that either the electric or the magnetic field dominates. We numerically show in the general case that the system can be well-approximated as a weighted sum of the two limits.

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Aaron Winn, John Maier, Andrew Jiao, Jeffrey C. Y. Teo. 2019-07-15. Magnetic Effects on Topological Chiral Channels in Bilayer Graphene. https://arxiv.org/abs/1907.06605

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