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arXiv · 2305.16576

Blue-detuned molecular magneto-optical trap schemes based on bayesian optimization

S. Xu·R. Li·Y. Zhai·Y. Xia·M. Siercke·S. Ospelkaus
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Abstract

Direct laser cooling and trapping of molecules to temperature below Doppler limit and density exceeding $10^8$ are challenging due to the sub-Doppler heating effects of molecular magneto-optical trap (MOT). In our previous paper [1], we presented a general approach to engineering the sub- Doppler force by tuning the AC stark shift with the addition of a blue detuned laser. Here, by employing the Bayesian optimization method to optical Bloch equations, we have identified multiple blue-detuned MOT schemes for the CaF molecule. From the three-dimensional Monte-Carlo simulation, we obtained a MOT temperature and density of 14 $\rm \mu K$ and $\rm 4.5 \times 10^8 cm^{-3}$, respectively. Our findings present a potential avenue for directly loading molecular MOTs into conservative traps, which can capitalize on the high density and low temperature of the MOT

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S. Xu, R. Li, Y. Zhai, Y. Xia, M. Siercke, S. Ospelkaus. 2023-05-26. Blue-detuned molecular magneto-optical trap schemes based on bayesian optimization. https://arxiv.org/abs/2305.16576

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