论文标题
开放量子系统非平衡稳态的响应理论
Response theory for nonequilibrium steady-states of open quantum systems
论文作者
论文摘要
我们在非平衡稳态中引入了一种受到哈密顿扰动的响应理论。在弱系统浴耦合方面工作，我们的结果是在Lindblad-Gorini-Kossakowski-Sudarshan形式主义中得出的。我们发现，与系统内部的相关函数相关，与封闭的系统中传统的线性响应理论或波动 - 散落定理的期望不同，系统对小扰动的响应不仅与系统中的相关函数有关。在限制情况下，当扰动相对于与周围环境的耦合或不导致系统特征结构的变化时，存在扰动膨胀，而响应函数与系统相关函数的总和和周围环境引起的其他力相关。但是，从这些限制方案中，世俗的近似导致奇异的响应无法在传统方法中捕获，但是可以通过恢复微观的哈密顿描述来描述。这些发现通过在不同温度下接触的耦合Qubits和Anharmonic振荡器中的显式计算来说明这些发现。
We introduce a response theory for open quantum systems within nonequilibrium steady-states subject to a Hamiltonian perturbation. Working in the weak system-bath coupling regime, our results are derived within the Lindblad-Gorini-Kossakowski-Sudarshan formalism. We find that the response of the system to a small perturbation is not simply related to a correlation function within the system, unlike traditional linear response theory in closed systems or expectations from the fluctuation-dissipation theorem. In limiting cases, when the perturbation is small relative to the coupling to the surroundings or when it does not lead to a change of the eigenstructure of the system, a perturbative expansion exists where the response function is related to a sum of a system correlation functions and additional forces induced by the surroundings. Away from these limiting regimes however, the secular approximation results in a singular response that cannot be captured within the traditional approach, but can be described by reverting to a microscopic Hamiltonian description. These findings are illustrated by explicit calculations in coupled qubits and anharmonic oscillators in contact with bosonic baths at different temperatures.
