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arXiv · 2208.07394

Continuous Raman sideband cooling beyond the Lamb-Dicke Regime in a trapped ion chain

Qiming Wu·Yue Shi·Jiehang Zhang
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Abstract

We report continuous Raman sideband cooling (CRSC) of a long ion chain to the motional ground state beyond the Lamb-Dicke (LD) regime. By driving multiple sideband transitions simultaneously, we show that nearly all axial modes of a 24-ion chain are cooled to the ground state, with an LD parameter as large as $\eta = 1.3$, spanning a frequency bandwidth of 4 MHz. Compared to traditional ground-state cooling methods such as pulsed sideband cooling or electromagnetic-induced-transparency (EIT) cooling, our method offers two key advantages: robustness to timing errors; and an ultra-wide bandwidth unlimited by the number of ions. This technique contributes as a crucial step for large-scale quantum information processing with linear ion chains and higher dimensions alike, and can be readily generalized to other atomic and molecular systems.

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Qiming Wu, Yue Shi, Jiehang Zhang. 2022-08-15. Continuous Raman sideband cooling beyond the Lamb-Dicke Regime in a trapped ion chain. https://arxiv.org/abs/2208.07394

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