Photoelectron imaging of resonance-enhanced multiphoton ionization and above-threshold ionization of ammonia molecules in a strong 800-nm laser pulse

Song Le-Le^{1, 2, 3}, Sun Ya-Nan^{1, 3}, Wang Yan-Hui⁴, Wang Xiao-Chun^{1, 3}, He Lan-Hai^{1, 3}, Luo Si-Zuo^{1, 3}, Hu Wen-Hui^{1, 3}, Tong Qiu-Nan^{1, 3}, Ding Da-Jun^{1, 3}, Liu Fu-Chun^{1, 3, †}

Electron kinetic energy distributions of NH₃ molecules at 800 nm. Laser intensities are 1.6×10¹³ W/cm², 1.9×10¹³ W/cm², 2.2×10¹³ W/cm², 2.5×10¹³ W/cm², 2.7×10¹³ W/cm², 3.1×10¹³ W/cm², 3.8×10¹³ W/cm², 4.4×10¹³ W/cm², 5.0×10¹³ W/cm², 5.7×10¹³ W/cm². Numbers 1–4 represent peaks 1−4, respectively. Vertical solid black line refers to a single photon energy of 1.55 eV.