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arXiv · 1911.05220

Cross-dimensional relaxation of $^7$Li-$^{87}$Rb atomic gas mixtures in a spherical-quadrupole magnetic trap

Fang Fang·Shun Wu·Aaron Smull·Joshua A. Isaacs·Yimeng Wang·Chris H. Greene·Dan M. Stamper-Kurn
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Abstract

We measure the interspecies interaction strength between $^7$Li and $^{87}$Rb atoms through cross-dimensional relaxation of two-element gas mixtures trapped in a spherical quadrupole magnetic trap. We record the relaxation of an initial momentum-space anisotropy in a lithium gas when co-trapped with rubidium atoms, with both species in the $|F=1, m_F = -1\rangle$ hyperfine state. Our measurements are calibrated by observing cross-dimensional relaxation of a $^{87}$Rb-only trapped gas. Through Monte Carlo simulations, we compare the observed relaxation to that expected given the theoretically predicted energy-dependent differential cross section for $^7$Li-$^{87}$Rb collisions. The experimentally observed relaxation occurs significantly faster than predicted theoretically, a deviation that appears incompatible with other experimental data characterising the $^7$Li-$^{87}$Rb molecular potential.

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Fang Fang, Shun Wu, Aaron Smull, Joshua A. Isaacs, Yimeng Wang, Chris H. Greene, Dan M. Stamper-Kurn. 2019-11-13. Cross-dimensional relaxation of $^7$Li-$^{87}$Rb atomic gas mixtures in a spherical-quadrupole magnetic trap. https://doi.org/10.1103/physreva.101.012703

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