Symmetry Violation in Bichromatic Ionization by a Free-Electron Laser: Photoelectron Angular Distribution and Spin Polarization

A fundamental phenomenon of coherent control is investigated theoretically using the example neon photoionization by bichromatic field a free-electron laser. system exposed to fields with commensurable frequencies loses some symmetry, which manifests itself in angular distribution and spin polarization electron emission. We predict several such effects, for example, violation symmetry respect plane perpendicular vector second harmonic appearance new components polarization. Furthermore, we very efficient via manipulation phase between harmonics. Experimental observation these effects accessible modern lasers operating extreme ultraviolet wavelength regime.