论文标题
关于非线性光学电导率的一般特性
On the general properties of non-linear optical conductivities
论文作者
论文摘要
光导率是表征当前对时间依赖电场响应的材料的基本定义特性。在这项工作中，遵循Kubo的反应理论的方法，我们研究了量子多体系统在平衡和非平衡中的非线性光学传导性的一般特性。我们从相关函数方面获得了第二阶光学电导率的表达，并提供了最近提出的广义kohn公式的扰动证明。我们还通过关注瞬时响应来讨论$ f $ - sum规则对非平衡设置的概括。
The optical conductivity is the basic defining property of materials characterizing the current response toward time-dependent electric fields. In this work, following the approach of Kubo's response theory, we study the general properties of the nonlinear optical conductivities of quantum many-body systems both in equilibrium and non-equilibrium. We obtain an expression of the second- and the third-order optical conductivity in terms of correlation functions and present a perturbative proof of the generalized Kohn formula proposed recently. We also discuss a generalization of the $f$-sum rule to a non-equilibrium setting by focusing on the instantaneous response.
