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arXiv · 2502.20794

Enhancing the coherence time of a neutral atom by an optical quartic trap

Haobo Chang·Zhuangzhuang Tian·Xin Lv·Mengna Yang·Zhihui Wang·Qi Guo·Pengfei Yang·Pengfei Zhang·Gang Li·Tiancai Zhang
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Abstract

The coherence time of an optically trapped neutral atom is a crucial parameter for quantum technologies. We found that optical dipole traps with higher-order spatial forms inherently offer lower decoherence rates compared to those with lower-order spatial forms. We formulated the decoherence rate caused by the variance of the differential energy shift and photon jumping rate. Then, we constructed blue-detuned harmonic and quartic optical dipole traps, and experimentally investigated the coherence time of a trapped single cesium atom. The experimental results qualitatively verified our theory. Our approach provides a novel method to enhance the coherence time of optically trapped neutral atoms.

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Haobo Chang, Zhuangzhuang Tian, Xin Lv, Mengna Yang, Zhihui Wang, Qi Guo, Pengfei Yang, Pengfei Zhang, Gang Li, Tiancai Zhang. 2025-02-28. Enhancing the coherence time of a neutral atom by an optical quartic trap. https://arxiv.org/abs/2502.20794

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