1P- and 2P-OBIC axial response of small area devices

Abstract

A simulation describing the axial response of a thin semiconductor device layer under one-photon and two-photon excitation by a focused Gaussian beam is presented. Devices with areas smaller than the focal spot were considered. The variation of the total induced current with the relative magnitudes of the 1P and 2P absorption coefficients were also examined. For a sample undergoing both processes, the one-photon process was found to easily dominate. It is also shown that decreasing the device area added to the axial localization of the OBIC signal, even for the onephoton process. In addition, displacing the sample away from the center of the excitation beam is shown to significantly affect the axial response only for smaller samples.