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arXiv · 1805.01896

Time-quasiperiodic topological superconductors with Majorana Multiplexing

Yang Peng·Gil Refael
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Abstract

Time-quasiperiodic Majoranas are generalizations of Floquet Majoranas in time-quasiperiodic superconducting systems. We show that in a system driven at $d$ mutually irrational frequencies, there are up to $2^d$ types of such Majoranas, coexisting despite spatial overlap and lack of time-translational invariance. Although the quasienergy spectrum is dense in such systems, the time-quasiperiodic Majoranas can be stable and robust against resonances due to localization in the periodic-drives induced synthetic dimensions. This is demonstrated in a time-quasiperiodic Kitaev chain driven at two frequencies. We further relate the existence of multiple Majoranas in a time-quasiperiodic system to the time quasicrystal phase introduced recently. These time-quasiperiodic Majoranas open a new possibility for braiding which will be pursued in the future.

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Yang Peng, Gil Refael. 2018-05-04. Time-quasiperiodic topological superconductors with Majorana Multiplexing. https://doi.org/10.1103/physrevb.98.220509

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