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arXiv · 2203.00877

Chiral-coupling-assisted refrigeration in trapped ions

Chi-Chih Chen·Yi-Cheng Wang·Chun-Che Wang·H. H. Jen
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Abstract

The tapped ions can be cooled close to their motional ground state, which is imperative in implementing quantum computation and quantum simulation. Here we demonstrate the capability of light-mediated chiral couplings between ions, which enables a superior cooling scheme exceeding the single-ion limit of sideband cooling. We present the chiral-coupling-assisted refrigeration in the target ion at the price of heating the others under asymmetric drivings, where its steady-state phonon occupation outperforms the lower bound set by a single ion. We further locate the optimal operation condition of the refrigeration and identify the parameter region where a faster rate of cooling emerges. Under an additional nonguided decay channel, the heating effect in the reciprocal coupling regime becomes suppressed and turns into cooling instead. Our results present a resource of collective chiral couplings which help surpass the bottleneck of cooling procedure in applications of trapped-ion-based quantum computer and simulator.

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Chi-Chih Chen, Yi-Cheng Wang, Chun-Che Wang, H. H. Jen. 2022-03-02. Chiral-coupling-assisted refrigeration in trapped ions. https://doi.org/10.1088/1361-6455/acc709

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