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arXiv · 1505.00738

Decoherence of Impurities in a Fermi Sea of Ultracold Atoms

Marko Cetina·Michael Jag·Rianne S. Lous·Jook T. M. Walraven·Rudolf Grimm·Rasmus S. Christensen·Georg M. Bruun
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Abstract

We investigate the decoherence of $^{40}$K impurities interacting with a three-dimensional Fermi sea of $^{6}$Li across an interspecies Feshbach resonance. The decoherence is measured as a function of the interaction strength and temperature using a spin-echo atom interferometry method. For weak to moderate interaction strengths, we interpret our measurements in terms of scattering of K quasiparticles by the Fermi sea and find very good agreement with a Fermi liquid calculation. For strong interactions, we observe significant enhancement of the decoherence rate, which is largely independent of temperature, pointing to behavior that is beyond the Fermi liquid picture.

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Marko Cetina, Michael Jag, Rianne S. Lous, Jook T. M. Walraven, Rudolf Grimm, Rasmus S. Christensen, Georg M. Bruun. 2015-05-04. Decoherence of Impurities in a Fermi Sea of Ultracold Atoms. https://doi.org/10.1103/physrevlett.115.135302

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