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Direct observation of Feshbach enhanced s-wave scattering of fermions



Dina Genkina, Lauren M. Aycock, Hsin I Lu, Ian B. Spielman, Benjamin K. Stuhl


We directly measured the s-wave scattering cross-section of ultracold 40K atoms across the 20.2 mT Feshbach resonance by colliding pairs of degenerate Fermi gases (DFGs) and imaging the scattered atoms. Owing to DFG’s low density, few atoms scattered, even near the resonance. To optimize signal to noise, we developed techniques to interpret absorption images in the regime where recoil induced detuning corrections are significant. By applying these techniques to our s-wave scattering data we extracted the resonant magnetic field value B0 = 20.247(2) mT and resonance width ∆ = 1.0(1) mT. These imaging techniques are generally applicable to experiments with light atoms in which maximizing the signal-to-noise ratio on the atom number counting is critical and imaging resolution can be sacrificed.
New Journal of Physics


Quantum gases, Atomic physics


Genkina, D. , Aycock, L. , , H. , Spielman, I. and Stuhl, B. (2015), Direct observation of Feshbach enhanced s-wave scattering of fermions, New Journal of Physics, [online], (Accessed April 17, 2024)
Created December 17, 2015, Updated February 19, 2017