论文标题
带有两体损失的费米子超流体的耗散动力学
Dissipative Dynamics of a Fermionic Superfluid with Two-Body Losses
论文作者
论文摘要
我们研究了在存在两体损失的情况下，费米子超流体的耗散动力学。我们使用一种变异方法来用于lindblad动力学，并为安德森的伪旋转获得动力学方程，其中耗散作为复杂的配对相互作用以及有效的，密度依赖性的，单个粒子损失，破坏了伪旋转型的保存。我们表明，后者对系统的动态行为有关键的后果。在两体损失突然切换的情况下，我们表明，超流体顺序参数的衰减速度比当时短时间粒子密度快得多，最终放慢了下降，将其设置为由系统耗尽驱动的较长时间尺度下的动力衰减。然后，我们考虑了配对相互作用的淬火，在单一情况下导致连贯的振荡，然后进行耗散的切换。我们表明，损失不仅引入阻尼，而且还对相干振荡的频率进行重新归一化，从而消除了动力学BCS同步，这与两体损失的速率非线性取决于。
We study the dissipative dynamics of a fermionic superfluid in presence of two-body losses. We use a variational approach for the Lindblad dynamics and obtain dynamical equations for Anderson's pseudo-spins where dissipation enters as a complex pairing interaction as well as effective, density-dependent, single particle losses which break the conservation of the pseudo-spin norm. We show that this latter has key consequences on the dynamical behavior of the system. In the case of a sudden switching of two-body losses we show that the superfluid order parameter decays much faster than then particle density at short times and eventually slows-down, setting into a power-law decay at longer time scales driven by the depletion of the system. We then consider a quench of pairing interaction, leading to coherent oscillations in the unitary case, followed by the switching of the dissipation. We show that losses wash away the dynamical BCS synchronization by introducing not only damping but also a renormalization of the frequency of coherent oscillations, which depends non-linearly from the rate of the two-body losses.
