标题： 脉冲宽度和失谐对相干声子生成的影响 显示英文标题

标题： Influence of pulse width and detuning on coherent phonon generation

摘要： 我们通过用超短脉冲照射，研究了相干声子的生成机制，采用了一个简单的双能级模型。 我们推导的公式表明，受激拉曼斯托克斯散射（ISRS）和受激吸收（IA）同时发生，ISRS和IA分别在电子基态和激发态中产生声子波包。 我们从声子振荡的振幅中确定了主要过程。 对于短脉冲宽度，ISRS非常小，随着脉冲宽度的增加而变大。 我们还表明，初始相位取决于脉冲宽度和失谐。 显示英文摘要

摘要： We investigated the coherent phonon generation mechanism by irradiation of an ultrashort pulse with a simple two-level model. Our derived formulation shows that both impulsive stimulated Raman scattering (ISRS) and impulsive absorption (IA) simultaneously occur, and phonon wave packets are generated in the electronic ground and excited states by ISRS and IA, respectively. We identify the dominant process from the amplitude of the phonon oscillation. For short pulse widths, ISRS is very small and becomes larger as the pulse width increases. We also show that the initial phase is dependent on the pulse width and the detuning.