论文标题
费米旋转二行子和耗散性费米 - 棕榈般的拉比动力学
Fermi spin polaron and dissipative Fermi-polaron Rabi dynamics
论文作者
论文摘要
我们考虑一种自旋杂质，其在非相互作用的费米海中移动的多个能级，理论上通过使用非元素持续的多体$ t $ -matrix理论来解决非零温度下的费米旋转极性问题。我们专注于最简单的旋转一半的情况，其中杂质的两个能量状态与狂犬翻转术语结合在一起。在小兔耦合时，杂质表现出阻尼的狂犬病振荡，在这种情况下，与费米海的相互作用引起的，在Fermi Polaron在用Ultracold Atoms进行的实验中报道。我们研究了拉比振荡对拉比耦合强度的依赖性，并检查由于大型兔耦合而引起的其他非线性阻尼。在有限温度和非零杂质浓度下，杂质可以获得明显的动量分布。我们表明，动量/热平均值可以大大降低拉比振荡的可见性。我们将理论预测与最近的实验数据进行比较，并找到一个良好的一致性，而没有任何可调节的参数。
We consider a spin impurity with multiple energy levels moving in a non-interacting Fermi sea, and theoretically solve this Fermi spin polaron problem at nonzero temperature by using a non-self-consistent many-body $T$-matrix theory. We focus on the simplest case with spin half, where the two energy states of the impurity are coupled by a Rabi flip term. At small Rabi coupling, the impurity exhibits damped Rabi oscillations, where the decoherence is caused by the interaction with the Fermi sea, as recently reported in Fermi polaron experiments with ultracold atoms. We investigate the dependence of Rabi oscillations on the Rabi coupling strength and examine the additional nonlinear damping due to large Rabi coupling. At finite temperature and at nonzero impurity concentration, the impurity can acquire a pronounced momentum distribution. We show that the momentum/thermal average can sizably reduce the visibility of Rabi oscillations. We compare our theoretical predictions to the recent experimental data and find a good agreement without any adjustable parameter.
