An intuitive and complete understanding of the underlying processes in high harmonic generation (HHG) in solids will enable the development and optimization of experimental techniques for attosecond measurement of dynamical and structural properties of solids. Here we introduce the Wannier quasi-classical (WQC) theory, which allows the characterization of HHG in terms of classical trajectories. The WQC approach completes the single-body picture for HHG in semiconductors, as it is in quantitative agreement with quantum calculations. The importance of WQC theory extends beyond HHG; it enables modeling of dynamic processes in solids with classical trajectories, such as for coherent control and transport processes, potentially providing better scalability and a more intuitive understanding.

中文翻译：

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Wannier准经典方法在半导体中产生高次谐波

对固体中高次谐波产生（HHG）的基本过程的直观而完整的理解将有助于开发和优化用于阿秒测量固体动力学和结构性质的实验技术。在这里，我们介绍了Wannier准经典（WQC）理论，该理论允许根据经典轨迹表征HHG。WQC方法完成了半导体中HHG的单体图像，因为它与量子计算在数量上是一致的。WQC理论的重要性超出了HHG。它可以对具有经典轨迹的实体中的动态过程进行建模，例如用于连贯的控制和传输过程，从而有可能提供更好的可伸缩性和更直观的理解。