Extreme multiphoton luminescence in GaAs. (17th October 2016) - Sabag, Evyatar
Abstract: We demonstrate experimentally extreme multiphoton-absorption cascades in GaAs. We show (2 + 3)- and (2 + 4)-photon luminescence, in which a two-photon transition occurs from the valence to the lower conduction band, followed by another 3- or 4-photon transition to the upper conduction band —inducing luminescence corresponding to several inter-band transitions in GaAs. Our systematic study of the observed effects verifies the cascaded multiphoton absorption, by monitoring the pump intensity and wavelength dependence of the observed luminescence spectra. The measurements are in good agreement with our modeling of multiphoton effects including Auger recombination. Our results open new directions in bulk-material band-structure exploration.