论文标题
Terahertz引起的高阶谐波产生和非线性电荷转运
Terahertz-induced high-order harmonic generation and nonlinear charge transport in graphene
论文作者
论文摘要
我们从理论上研究了基于量子的量子近似值，基于量子主方程，石墨烯中THZ诱导的高阶谐波产生（HHG）和非线性电运输。为了获得对该现象的微观见解，我们将完全动态计算的结果与准静态近似的结果进行比较，其中电子系统被视为非平衡稳态。结果，我们发现在每个实例上，可以用非平衡稳态对石墨烯中THZ诱导的电子动力学进行准确建模。人口分布分析进一步阐明了石墨烯中THZ诱导的HHG源自布里鲁因地区电子大量位移而导致有效电导率的降低。通过将当前的非平衡图像与热力学图片进行比较，我们探讨了电子动力学对石墨烯中极为非线性光学和传输现象的非平衡性质的作用。
We theoretically study the THz-induced high-order harmonic generation (HHG) and nonlinear electric transport in graphene based on the quantum master equation with the relaxation time approximation. To obtain microscopic insight into the phenomena, we compare the results of the fully dynamical calculations with those under a quasi-static approximation, where the electronic system is approximated as a nonequilibrium steady state. As a result, we find that the THz-induced electron dynamics in graphene can be accurately modeled with the nonequilibrium steady-state at each instance. The population distribution analysis further clarifies that the THz-induced HHG in graphene originates from the reduction of effective conductivity due to a large displacement of electrons in the Brillouin zone. By comparing the present nonequilibrium picture with a thermodynamic picture, we explore the role of the nonequilibrium nature of electron dynamics on the extremely nonlinear optical and transport phenomena in graphene.
