摘要
We theoretically study the photoelectron momentum distributions from multiphoton ionization of a model lithium atom over a range of laser wavelengths from 500 nm to 700 nm by numerically solving the time-dependent Schr ¨odinger equation. The photoelectron momentum distributions display many ring-like patterns for the three-photon ionization, which vary dramatically with the change of the laser wavelength. We show that the wavelength-dependent photoelectron energy spectrum can be used to effectively identify the resonant and nonresonant ionization pathways. We also find an abnormal ellipticity dependence of the electron yield for the(2+1) resonance-enhanced ionization via the 4d intermediate state, which is relevant to the two-photon excitation probability from the ground state to the 4d state.
作者
郭珂雨
黎敏
梁锦台
曹传鹏
周月明
陆培祥
Keyu Guo;Min Li;Jintai Liang;Chuanpeng Cao;Yueming Zhou;Peixiang Lu(School of Physics and Wuhan National Laboratory for Optoelectronics,Huazhong University of Science and Technology,Wuhan 430074,China;Optics Valley Laboratory,Wuhan 430074,China)
基金
supported by National Key Research and Development Program of China (Grant No. 2019YFA0308300)
the National Natural Science Foundation of China (Grant Nos. 12021004 and 61475055)。