论文标题
量子相干性和速度限制的均值超高模型
Quantum coherence and speed limit in the mean-field Dicke model of superradiance
论文作者
论文摘要
Dicke超级稳态是一种合作现象，它是由原子集合与电磁辐射的集体耦合产生的。在这里，我们讨论了平均场近似中的dicke超高模型的量子相干性的量化。我们发现，连贯性的单原子$ l_1 $ norm是由超级系统发出的辐射平均辐射平均强度的平方根给出的。这将量子相干性验证为在平均场方法中理解超沉载现象的有用数字。特别是，该结果表明，通过超级系统中的辐射强度探测单原子的相干性，这在实验实现中可能很有用，而在实验实现中，该实现无法单独解决原子。此外，考虑到有效描述$ n $原子系统的时间依赖性单原子状态的非线性统一动力学，我们分析了量子速度限制时间及其与$ l_1 $ norm of Cooherence的相互作用。我们验证量子相干性加快了超级系统的演变，即存储在单原子状态上的相干性越多，进化速度就越快。这些发现揭示了量子相干性在超级系统中所起的作用，这反过来又可能对凝聚态物理和量子光学的社区感兴趣。
Dicke superrandiance is a cooperative phenomenon which arises from the collective coupling of an ensemble of atoms to the electromagnetic radiation. Here we discuss the quantifying of quantum coherence for the Dicke model of superradiance in the mean-field approximation. We found the single-atom $l_1$-norm of coherence is given by the square root of the normalized average intensity of radiation emitted by the superradiant system. This validates quantum coherence as a useful figure of merit towards the understanding of superradiance phenomenon in the mean-field approach. In particular, this result suggests probing the single-atom coherence through the radiation intensity in superradiant systems, which might be useful in experimental realizations where is unfeasible to address atoms individually. Furthermore, given the nonlinear unitary dynamics of the time-dependent single-atom state that effectively describes the system of $N$ atoms, we analyze the quantum speed limit time and its interplay with the $l_1$-norm of coherence. We verify the quantum coherence speeds up the evolution of the superradiant system, i.e., the more coherence stored on the single-atom state, the faster the evolution. These findings unveil the role played by quantum coherence in superradiant systems, which in turn could be of interest for communities of both condensed matter physics and quantum optics.
