Photoemission with Picosecond Lasers: Fast Electron IDynamics at the GaAs (110) Surface

Subpicosecond pulses of 10.7 eV radiation from a tunable laser-based source free used to carry out photoemission investigations of the electronic dynamics on the laser-excited surface of GaAs (110). Angie-resolved studies have revealed a rapid surface intervalley scattering process that transfers electrons between the directly excited, surface Brillouin zone center to a previously unobserved valley within the bandgap at X, the surface zone edge. The scattering time has been determined to be 0.4 ± 0.1 ps. A model that describes the scattering dynamics is presented. © 1989 IEEE