Extreme multiphoton luminescence in GaAs
Department of Electrical Engineering, Technion - Haifa 32000, Israel
Received: 23 July 2016
Accepted: 21 September 2016
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.
PACS: 79.20.Ws – Multiphoton absorption / 42.50.Hz – Strong-field excitation of optical transitions in quantum systems; multiphoton processes; dynamic Stark shift / 78.55.Cr – III-V semiconductors
© EPLA, 2016