Spatially resolved pump-probe second harmonic generation study of multilayer semiconductor heterostructures

摘要

The transient electric-field-induced second harmonic generation change (TEFISHGC) signals from GaAs/GaSb/InAs heterostructures measured in pump-probe configuration have been applied to monitor the interfacial electric fields arising from the charge separation of pump-induced carriers at the interfaces. The total intensity of the TEFISHGC signal is determined by the interference of contributions from both of the heterointerfaces. By changing the photon energy of the laser light over the GaAs absorption edge, the depth spatial resolution can be achieved allowing the ultrafast dynamics of interfacial electric field at each of the interfaces to be monitored separately.