【摘要】 理论上证明了测量脉冲对激发的相干态布居等价于测量单脉冲激发的感应极化 ,能同时获得瞬态相干光学过程的振幅与相位信息 ,发展了双通道飞秒脉冲对实验技术 ,提出了相位差分光谱实验方法。研究了半导体 Ga As和稀土材料的飞秒相干态动力学过程 ,根据自相关曲线和样品信号的关系得到相位光谱。理论拟合得液氮温度下 Ga As的激子退相时间为 1 90 fs;单晶 Nd:YVO4 和粉末 Nd:YAG 4 f电子在室温下的退相时间为 3 0 0 fs。并研究了液氮温度下稀土材料原子核波包的动力学过程。更多还原

【Abstract】 It is proved that both amplitude and phase in instantaneous optical processes can be detected from the number density of the excited state populations of coherent carriers when excited with femtosecond laser pulse pairs. Experimental technique of phase spectroscopy is used for investigations of semiconductor GaAs and rare earth solids. Phase spectra of GaAs, crystal Nd:YVO 4 and powdered Nd:YAG are obtained. Dephasing time of GaAs exciton is 190fs at 77K and the Nd:YVO 4 and Nd:YAG are 300fs at room temperature.更多还原