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arXiv:1802.01954 · Physical Review Letters

Probing the Interface of a Phase-Separated State in a Repulsive Bose-Fermi Mixture

Rianne S. Lous, Isabella Fritsche, Michael Jag, Fabian Lehmann, Emil Kirilov, Bo Huang, Rudolf Grimm

Published Jun 13, 2018• 75 citations
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Abstract

We probe the interface between a phase-separated Bose-Fermi mixture consisting of a small Bose-Einstein condensate of ^{41}K residing in a large Fermi sea of ^{6}Li. We quantify the residual spatial overlap between the two components by measuring three-body recombination losses for variable strength of the interspecies repulsion. A comparison with a numerical mean-field model highlights the importance of the kinetic energy term for the condensed bosons in maintaining the thin interface far into the phase-separated regime. Our results demonstrate a corresponding smoothing of the phase transition in a system of finite size.

DOI
10.1103/physrevlett.120.243403

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