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arXiv · 2202.03355

A High Phase-Space Density Gas of NaCs Feshbach Molecules

Aden Z. Lam·Niccolò Bigagli·Claire Warner·Weijun Yuan·Siwei Zhang·Eberhard Tiemann·Ian Stevenson·Sebastian Will
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Abstract

We report on the creation of ultracold gases of bosonic Feshbach molecules of NaCs. The molecules are associated from overlapping gases of Na and Cs using a Feshbach resonance at 864.12(5) G. We characterize the Feshbach resonance using bound state spectroscopy, in conjunction with a coupled-channel calculation. By varying the temperature and atom numbers of the initial atomic mixtures, we demonstrate the association of NaCs gases over a wide dynamic range of molecule numbers and temperatures, reaching 70 nK for our coldest systems and a phase-space density near 0.1. This is an important stepping-stone for the creation of degenerate gases of strongly dipolar NaCs molecules in their absolute ground state.

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Aden Z. Lam, Niccolò Bigagli, Claire Warner, Weijun Yuan, Siwei Zhang, Eberhard Tiemann, Ian Stevenson, Sebastian Will. 2022-02-07. A High Phase-Space Density Gas of NaCs Feshbach Molecules. https://doi.org/10.1103/physrevresearch.4.l022019

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