We develop a model potential to simulate the effective potential of a single active electron in monolayer graphene by taking the electron energy band structure calculated by the density functional theory (DFT) as a reference. Based on the single-electron Schrödinger equation, the model potential is used to calculate not only the energy band structure but also the transition dipole moment, charge density, and other physical quantities of graphene. These quantities are compared with results from DFT and a good consistency is achieved. The simulation of laser-graphene interaction with the same laser parameters as Yoshikawa et al. [Science 356, 736 (2017)] is performed with the time-dependent Schrödinger equation. The obtained driving laser ellipticity scaling, the harmonic ellipticity, and the harmonic major-axis angle can well reproduce the experimental results. It is found that the carrier-envelope phase and chirp effects are capable of regulating high-order harmonic generation in monolayer graphene. The model potential method can be extended to field-free calculations and dynamic simulations in other materials as long as the corresponding model potential is constructed.

中文翻译：

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单层石墨烯高次谐波产生的模型势方法

我们以密度泛函理论（DFT）计算的电子能带结构为参考，建立了模型电势来模拟单活性石墨在单层石墨烯中的有效电势。基于单电子薛定er方程，模型势不仅用于计算能带结构，而且还用于计算跃迁偶极矩，电荷密度和其他石墨烯物理量。将这些数量与DFT的结果进行比较，可以实现良好的一致性。模拟激光-石墨烯相互作用的激光参数与Yoshikawa等人相同。[科学 356，736（2017）]随时间变化的薛定er方程执行。所获得的驱动激光椭圆度标度，谐波椭圆度和谐波主轴角可以很好地再现实验结果。发现载流子包络相和线性调频效应能够调节单层石墨烯的高次谐波产生。只要构建了相应的模型电势，模型电势方法就可以扩展到其他材料的无场计算和动态仿真。