标题： 具有移动杂质的1D费米气体中的关联退相干和测温 显示英文标题

标题： Correlated decoherence and thermometry with mobile impurities in a 1D Fermi gas

摘要： 我们理论研究了被束缚在超冷费米原子气体中的两个移动杂质的关联退相干动力学。 我们使用平均场近似自洽地描述杂质-气体碰撞对杂质运动的影响，而杂质内部状态的退相干则在功能行列式方法中精确计算。 在平衡状态下，我们发现当杂质-气体相互作用强度增加时，杂质会经历由环境引起的局域化。 随后，我们研究了由于杂质内部状态突然变化所引起的非平衡动力学，这可以通过Ramsey干涉测量实验进行探测。 我们的理论方法使我们能够研究杂质运动对退相干动力学的影响，发现当杂质与气体原子的质量不平衡较小时，会出现与安德森正交性灾难相关的普遍行为的强烈偏差。 最后，我们表明移动杂质可以作为其环境的温度计，并且即使在存在复杂杂质运动的情况下，浴介导的相关性在低温下仍能提高温度计的性能。 我们的结果展示了移动杂质在共同环境中去相位的有趣开放量子动力学，并可能有助于提供超冷费米混合物更精确的温度估计。 显示英文摘要

摘要： We theoretically investigate the correlated decoherence dynamics of two mobile impurities trapped within a gas of ultracold fermionic atoms. We use a mean-field approximation to self-consistently describe the effect of impurity-gas collisions on impurity motion, while decoherence of the impurities' internal state is computed exactly within a functional determinant approach. At equilibrium, we find that the impurities undergo bath-induced localisation as the impurity-gas interaction strength is increased. We then study the non-equilibrium dynamics induced by a sudden change of the impurities' internal state, which can be experimentally probed by Ramsey interferometry. Our theoretical approach allows us to investigate the effect of impurity motion on decoherence dynamics, finding strong deviations from the universal behaviour associated with Anderson's orthogonality catastrophe when the mass imbalance between impurity and gas atoms is small. Finally, we show that mobile impurities can be used as thermometers of their environment and that bath-mediated correlations can be beneficial for thermometric performance at low temperatures, even in the presence of non-trivial impurity motion. Our results showcase the interesting open quantum dynamics of mobile impurities dephasing in a common environment, and could help provide more precise temperature estimates of ultracold fermionic mixtures.