Topological Valley Currents in Gapped Dirac Materials
Gapped 2D Dirac materials, in which inversion symmetry is broken by a gap-opening perturbation, feature a unique valley transport regime. Topological valley currents in such materials are dominated by bulk currents produced by electronic states just beneath the gap rather than by edge modes. The sys...
Main Authors: | , , , |
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Other Authors: | |
Format: | Article |
Language: | English |
Published: |
American Physical Society
2015
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Online Access: | http://hdl.handle.net/1721.1/97542 https://orcid.org/0000-0002-4268-731X |
Summary: | Gapped 2D Dirac materials, in which inversion symmetry is broken by a gap-opening perturbation, feature a unique valley transport regime. Topological valley currents in such materials are dominated by bulk currents produced by electronic states just beneath the gap rather than by edge modes. The system ground state hosts dissipationless persistent valley currents existing even when topologically protected edge modes are absent. Valley currents induced by an external bias are characterized by a quantized half-integer valley Hall conductivity. The undergap currents dominate magnetization and the charge Hall effect in a light-induced valley-polarized state. |
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