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arXiv · 1510.00036

Direct observation of Feshbach enhanced $\it{s}$-wave scattering of fermions

Dina Genkina·Lauren M. Aycock·Benjamin K. Stuhl·Hsin-I Lu·Ross A. Williams·Ian B. Spielman
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Abstract

We directly measured the normalized $\it{s}$-wave scattering cross-section of ultracold $^{40}\rm{K}$ atoms across a magnetic-field Feshbach resonance by colliding pairs of degenerate Fermi gases (DFGs) and imaging the scattered atoms. We extracted the scattered fraction for a range of bias magnetic fields, and measured the resonance location to be $B_0 = 20.206(15)$ mT with width $Δ= 1.0(5)$ mT. To optimize the signal-to-noise ratio of atom number in scattering images, we developed techniques to interpret absorption images in a regime where recoil induced detuning corrections are significant. These imaging techniques are generally applicable to experiments with lighter alkalis that would benefit from maximizing signal-to-noise ratio on atom number counting at the expense of spatial imaging resolution.

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Dina Genkina, Lauren M. Aycock, Benjamin K. Stuhl, Hsin-I Lu, Ross A. Williams, Ian B. Spielman. 2015-10-08. Direct observation of Feshbach enhanced $\it{s}$-wave scattering of fermions. https://arxiv.org/abs/1510.00036

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