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arXiv · 2103.10628

Fisher zeros and persistent temporal oscillations in non-unitary quantum circuits

Sankhya Basu·Daniel P. Arovas·Sarang Gopalakrishnan·Chris A. Hooley·Vadim Oganesyan
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Abstract

We present a quantum circuit with measurements and post-selection that exhibits a panoply of space- and/or time-ordered phases, from ferromagnetic order to spin-density waves to time crystals. Unlike the time crystals that have been found in unitary models, those that occur here are \emph{incommensurate} with the drive frequency. The period of the incommensurate time-crystal phase may be tuned by adjusting the circuit parameters. We demonstrate that the phases of our quantum circuit, including the inherently non-equilibrium dynamical ones, correspond to complex-temperature equilibrium phases of the exactly solvable square-lattice anisotropic Ising model.

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Sankhya Basu, Daniel P. Arovas, Sarang Gopalakrishnan, Chris A. Hooley, Vadim Oganesyan. 2021-03-19. Fisher zeros and persistent temporal oscillations in non-unitary quantum circuits. https://doi.org/10.1103/physrevresearch.4.013018

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