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arXiv · 1406.3633

Dynamical response of dissipative helical edge states

Doru Sticlet·Jérôme Cayssol
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Abstract

Quantum spin Hall insulators are characterized by topologically protected counterpropagating edge states. Here we study the dynamical response of these helical edge states under a time-dependent flux biasing, in the presence of a heat bath. It is shown that the relaxation time of the edge carriers can be determined from a measurement of the dissipative response of topological insulator disks. The effects of various perturbations, including Zeeman coupling and disorder, are also discussed.

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Doru Sticlet, Jérôme Cayssol. 2014-06-13. Dynamical response of dissipative helical edge states. https://doi.org/10.1103/physrevb.90.201303

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