Discrete Time Crystals in the spin-s Central Spin Model

Hillol Biswas; Sayan Choudhury

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arXiv · 2505.13207

Discrete Time Crystals in the spin-s Central Spin Model

Hillol Biswas·Sayan Choudhury

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Abstract

We propose periodic driving protocols to realize discrete time crystals (DTCs) in a spin-s central spin model. Interestingly, we identify parameter regimes, where eternal period-doubling and higher-order(HO)-DTCs can be realized, even for finite-sized systems. We have determined the dependence of the DTC order on the number of satellite spins and the central spin value, s. Intriguingly, we find that certain classes of HO-DTCs produce a series of maximally entangled Bell cat and super-cat states during their dynamical evolution. Finally, we demonstrate that the HO-DTCs can be employed for quantum-enhanced multiparameter sensing at the Heisenberg limit.

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Hillol Biswas, Sayan Choudhury. 2025-05-19. Discrete Time Crystals in the spin-s Central Spin Model. https://arxiv.org/abs/2505.13207

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