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arXiv · 2201.07578

Dynamical construction of Quadrupolar and Octupolar topological superconductors

Arnob Kumar Ghosh·Tanay Nag·Arijit Saha
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Abstract

We propose a three-step periodic drive protocol to engineer two-dimensional~(2D) Floquet quadrupole superconductors and three-dimensional~(3D) Floquet octupole superconductors hosting zero-dimensional Majorana corner modes~(MCMs), based on unconventional $d$-wave superconductivity. Remarkably, the driven system conceives four phases with only $0$ MCMs, no MCMs, only anomalous $\pi$ MCMs, and both regular $0$ and anomalous $\pi$ MCMs. To circumvent the subtle issue of characterizing $0$ and $\pi$ MCMs separately, we employ the periodized evolution operator to architect the dynamical invariants, namely quadrupole and octupole motion in 2D and 3D, respectively, that can distinguish different higher order topological phases unambiguously.Our study paves the way for the realization of dynamical quadrupolar and octupolar topological superconductors.

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Arnob Kumar Ghosh, Tanay Nag, Arijit Saha. 2022-01-19. Dynamical construction of Quadrupolar and Octupolar topological superconductors. https://doi.org/10.1103/physrevb.105.155406

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