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arXiv · 1908.11719

Transport signatures of a Floquet topological transition at the helical edge

C. Fleckenstein·N. Traverso Ziani·L. Privitera·M. Sassetti·B. Trauzettel
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Abstract

The manipulation of the helical edge states of two-dimensional topological insulators is crucial for the development of technological applications. Recently, an important step forward, namely, the experimental realization of a quantum point contact between helical edges, has been accomplished. We theoretically predict that such a quantum point contact, in the presence of a time periodic applied electric field, is characterized by a topological quantum phase transition in the Floquet spectrum. Moreover, we show that it is possible to detect this dynamical topological quantum phase transition by a bare conductance measurements.

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C. Fleckenstein, N. Traverso Ziani, L. Privitera, M. Sassetti, B. Trauzettel. 2019-08-30. Transport signatures of a Floquet topological transition at the helical edge. https://doi.org/10.1103/physrevb.101.201401

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