Institut für Quantenoptik und Quanteninformation (IQOQI), Österreichische Akademie der Wissenschaften, 6020 Innsbruck, Austria.
Institut für Experimentalphysik, Universität Innsbruck, 6020 Innsbruck, Austria.
Phys Rev Lett. 2018 Jun 15;120(24):243403. doi: 10.1103/PhysRevLett.120.243403.
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.
我们探究了由一小部分处于 ^{41}K 玻色-爱因斯坦凝聚态的玻色子和大部分 ^{6}Li 费米子组成的分相玻色-费米混合物的界面。我们通过测量三体复合损耗来量化两种成分之间的剩余空间重叠，其大小取决于物种间排斥力的强度。与数值平均场模型的比较突出了凝聚玻色子的动能项在维持分相区中薄界面方面的重要性。我们的结果表明，在有限尺寸的系统中，相变会相应地变得平滑。
