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arXiv · 2405.13645

Formation and Dissociation of Field-Linked Tetramers

Fulin Deng·Xing-Yan Chen·Xin-Yu Luo·Wenxian Zhang·Su Yi·Tao Shi
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Abstract

We investigate the static and dynamic properties of tetratomic molecules formed by two microwave-shielded polar molecules across field-linked resonances. In particular, we focus on two-body physics and experimental techniques unexplored in the recent experiment [X.-Y. Chen {\it et al}., Nature {\bf626}, 283 (2024)]. We show that, compared to the lowest tetramer state, higher tetramer states typically have longer lifetimes, which may facilitate a further cooling of tetramer gases towards quantum degeneracy. To detect tetramers, we identify the distinctive time-of-flight images from ramp dissociation, which can be observed by lowering the ramp rate of the microwave. Remarkably, in the modulational dissociation of tetramers, we find that multi-photon processes induce dissociation even below the threshold modulation frequency when the modulation amplitude is sufficiently high. Given the universal form of the inter-molecular potential for microwave-shielded polar molecules, our results also apply to other molecular gases widely explored in recent experiments.

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Fulin Deng, Xing-Yan Chen, Xin-Yu Luo, Wenxian Zhang, Su Yi, Tao Shi. 2024-05-22. Formation and Dissociation of Field-Linked Tetramers. https://arxiv.org/abs/2405.13645

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