Interband resonances in the optical second-harmonic response of the (001) GaAs-oxide interface

摘要

The optical second-harmonic (SH) signal generated at the GaAs-oxide interface on N+, P+, and semiinsulating GaAs (001) surfaces has been measured for SH photon energies between 2.7 and 3.5 eV. The magnitude and the phase of the interfacial SH response reveal the presence of two strong resonances at SK photon energies corresponding to the E-1 and E-1 + Delta(1) interband transitions at 2.9 and 3.2 eV. These resonances dominate the N+ and semi-insulating GaAs spectra but are absent for P+-GaAs. Evidence suggests that the resonances are related to the structure of the GaAs-oxide interface. (C) 1997 Optical Society of America.