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arXiv · 2012.00762

Anomalous Floquet Chiral Topological Superconductivity in a Topological Insulator Sandwich Structure

Rui-Xing Zhang·S. Das Sarma
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Abstract

We show that Floquet chiral topological superconductivity arises naturally in Josephson junctions made of magnetic topological insulator-superconductor sandwich structures. The Josephson phase modulation associated with an applied bias voltage across the junction drives the system into the anomalous Floquet chiral topological superconductor hosting chiral Majorana edge modes in the quasienergy spectrum, with the bulk Floquet bands carrying zero Chern numbers. The bias voltage acts as a tuning parameter enabling novel dynamical topological quantum phase transitions driving the system into a myriad of exotic Majorana-carrying Floquet topological superconducting phases. Our theory establishes a new paradigm for realizing Floquet chiral topological superconductivity in solid-state systems, which should be experimentally directly accessible.

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Rui-Xing Zhang, S. Das Sarma. 2020-12-01. Anomalous Floquet Chiral Topological Superconductivity in a Topological Insulator Sandwich Structure. https://doi.org/10.1103/physrevlett.127.067001

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