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arXiv · 2205.06441

Emergence and Dynamical Stability of Charge Time-Crystal in a Current-Carrying Quantum Dot Simulator

Subhajit Sarkar·Yonatan Dubi
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Abstract

Periodically-driven open quantum systems that never thermalize exhibit a discrete time-crystal behavior, a non-equilibrium quantum phenomenon that has shown promise in quantum information processing applications. Measurements of time-crystallinity are currently limited to (magneto-) optical experiments in atom-cavity systems and spin-systems making it an indirect measurement. We theoretically show that time-crystallinity can be measured directly in the charge-current from a spin-less Hubbard ladder, which can be simulated on a quantum-dot array. We demonstrate that one can dynamically tune the system out and then back into the time-crystal phase, proving its robustness against external forcings. These findings motivate further theoretical and experimental efforts to simulate the time-crystal phenomena in current-carrying nano-scale systems.

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Subhajit Sarkar, Yonatan Dubi. 2022-05-13. Emergence and Dynamical Stability of Charge Time-Crystal in a Current-Carrying Quantum Dot Simulator. https://doi.org/10.1021/acs.nanolett.2c00976

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