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arXiv · 2003.06828

Topological quantum control: Edge currents via Floquet depinning of skyrmions in the $\nu = 0$ graphene quantum Hall antiferromagnet

Deepak Iyer·Matthew S. Foster
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Abstract

We propose a defect-to-edge topological quantum quench protocol that can efficiently inject electric charge from defect-core states into a chiral edge current of an induced Chern insulator. The initial state of the system is assumed to be a Mott insulator, with electrons bound to topological defects that are pinned by disorder. We show that a "critical quench" to a Chern insulator mass of order the Mott gap shunts charge from defects to the edge, while a second stronger quench can trap it there and boost the edge velocity, creating a controllable current. We apply this idea to a skyrmion charge in the $\nu = 0$ quantum Hall antiferromagnet in graphene, where the quench into the Chern insulator could be accomplished via Floquet driving with circularly polarized light.

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Deepak Iyer, Matthew S. Foster. 2020-03-15. Topological quantum control: Edge currents via Floquet depinning of skyrmions in the $\nu = 0$ graphene quantum Hall antiferromagnet. https://doi.org/10.1103/physrevb.101.241403

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