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arXiv · 2501.14303

Anomalies in the rotational spectra of $^{86}$Sr ULRRM dimers

C. Wang·Y. Lu·A. Li·S. K. Kanungo·T. C. Killian·F. B. Dunning·S. Yoshida
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Abstract

Anomalies in the rotational structure of $^{86}$Sr $^3S_1$ dimer ultralong-range Rydberg molecules (ULRRMs) created in a cold strontium gas by two-photon excitation via the intermediate $5s5p~^3P_1$ state are reported. Measurements reveal that the distribution of product rotational states is sensitive to intermediate state detuning. Comparative studies using $^{84}$Sr $^1S_0$ and $^3S_1$, and $^{86}$Sr $^1S_0$ dimers display no similar behavior, indicating that the observed behavior is peculiar to $^{86}$Sr triplet dimers. While we have no definitive hypothesis as to the physical mechanism responsible for this behavior, possible explanations might involve the very different scattering lengths for $^{84}$Sr and $^{86}$Sr, or the interchange of spin and rotational angular momentum.

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C. Wang, Y. Lu, A. Li, S. K. Kanungo, T. C. Killian, F. B. Dunning, S. Yoshida. 2025-01-24. Anomalies in the rotational spectra of $^{86}$Sr ULRRM dimers. https://arxiv.org/abs/2501.14303

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