Mechanisms on the Photoelectron Angular Distributions of Atoms Ionized in Mid-Infrared Laser Fields

[摘要] By solving the time-dependent Schrodinger equation, we show conclusively that low energy/momenta structure in the photoelectron angular distribution originates from multiple scatterings of the tunnel-ionized electron with the ion. We also show that two conditions must be satisfied simultaneously in order to observe prominent low-energy features. First, multiple scattering of the tunnel-ionized electron wave packet is necessary. Second, tunnel ionization must dominate over multiphoton ionization. While the first condition is generally satisfied for all laser wavelengths, the second condition is satisfied only for longer laser wavelengths.

[发布机构] Division of Materials Science, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki; 305-8577, Japan^1;JILA, Department of Physics, University of Colorado at Boulder, Boulder; CO; 80309, United States^2;Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley; CA; 94720, United States^3

[关键词] Ionized electrons;Laser wavelength;Low-energy;Midinfrared lasers;Multiphoton ionization;Photoelectron angular distributions;Time dependent Schrodinger equation;Tunnel ionization