Mainz 2017 – wissenschaftliches Programm
Q 46.6: Vortrag
Donnerstag, 9. März 2017, 12:30–12:45, P 204
Phase Separation in a Bose-Fermi Mixture of 41K and 6Li — •Rianne S. Lous1,2, Bo Huang1, Isabella Fritsche1,2, Fabian Lehmann1,2, Michael Jag1,2, Emil Kirilov1,2, and Rudolf Grimm1,2 — 1IQOQI, Austrian Academy of Sciences, Innsbruck, Austria — 2Institute for Experimental Physics, University of Innsbruck, Innsbruck, Austria
We report on the observation of phase separation between a 41K Bose-Einstein condensate (BEC) and a 6Li Fermi sea with strong repulsive interspecies interactions. After evaporation in an optical dipole trap, we obtain 104 41K atoms with a 55 % BEC fraction and a Fermi sea of 105 6Li atoms with a T/TF < 0.07. We explore this double-degenerate mixture by tuning the heternonuclear interaction with the use of a Feshbach resonance at 335.8 G. We observe the phase separation by measuring the breathing-mode frequency of the bosons and their lifetimes for varying interaction strength. We see an increase in frequency when interactions become strongly repulsive and a decrease in loss rate. To understand our loss rate results, we calculate the spatial overlap between the two components with a mean-field model beyond local density approximation (LDA) and attribute the losses to the three-body recombination. We also calculate the breathing-mode frequency on a LDA level. Both theoretical models fit nicely to our experimental results. This work is supported by the Austrian Science Fund FWF within SFB FoQuS.