Anomalous Floquet Chiral Topological Superconductivity in a Topological Insulator Sandwich Structure

TL;DR

This paper demonstrates that applying a bias voltage to magnetic topological insulator-superconductor Josephson junctions induces Floquet chiral topological superconductivity with Majorana edge modes, enabling dynamic topological phase transitions.

Contribution

It introduces a new method to realize Floquet chiral topological superconductivity in solid-state systems using Josephson junctions with magnetic topological insulators.

Findings

Bias voltage induces Floquet chiral topological phases.

Presence of chiral Majorana edge modes.

Multiple exotic Floquet topological phases achievable.

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.