Identification of Above-Threshold Ionization by Imaging Photoelectrons from Ammonia Molecules in an Intense Femtosecond Laser Field

• 作者: Qin Yang Jing Leng Yan-Hui Wang Ya-Nan Sun Hai-Bin Du Dong-Dong Zhang Le-Le Song Lan-Hai He Fu-Chun Liu
• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2022,（2）
• 所属期刊栏目: ATOMIC AND MOLECULAR PHYSICS
• 页码范围: 33-40
• 页数: 8页
• 语种: 英文
• DOI: 10.1088/0256-307X/39/2/023301

摘要

The above-threshold ionization process of ammonia molecules induced by a femtosecond laser field at 800 nm is studied in the intensity range from 1.6 × 1013 to 5.7 × 1013 W/cm2.Channel switching under different laser intensities is observed and identified in the photoelectron kinetic energy spectra of ammonia.Based on the photoelectron kinetic energy distributions and the photoelectron angular distributions,the characteristic peaks observed are exclusively assigned to the multiphoton resonance through certain intermediate states,followed by multiphoton above-threshold ionization.