Photo-induced Superconductivity = Discrete Time Crystal?

Zhehao Dai; Vibhu Ravindran; Norman Y. Yao; Michael P. Zaletel

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arXiv · 2209.05510

Photo-induced Superconductivity = Discrete Time Crystal?

Zhehao Dai·Vibhu Ravindran·Norman Y. Yao·Michael P. Zaletel

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Abstract

We propose that periodic driving can stabilize a new type of order, "period-doubled superconductivity", in which a superconducting order parameter oscillates at half the frequency of the drive. Despite having a zero time-averaged order parameter, the ordered state exhibits perfect conductivity and a Meissner effect. Our theory predicts that this phase may be realized as the steady state of materials shown to exhibit photo-induced superconductivity. We propose to detect the period-doubled oscillation of the order parameter by utilizing a Josephson junction between a photo-induced superconductor and a conventional superconductor. Our theory can also be realized via parametric driving of cold bosonic atoms in an optical lattice.

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cond-mat.supr-con cond-mat.mes-hall cond-mat.quant-gas cond-mat.stat-mech cond-mat.str-el

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Zhehao Dai, Vibhu Ravindran, Norman Y. Yao, Michael P. Zaletel. 2022-09-12. Photo-induced Superconductivity = Discrete Time Crystal?. https://arxiv.org/abs/2209.05510

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