Ultrafast all-optical switching in one-dimensional photonic crystal with two defects

Abstract

One-dimensional (1D) photonic crystals (PC) containing two-layer CdS defects are proposed and fabricated by using electron beam evaporation. Ultrafast nonlinear optical responses were characterized with the ultrafast pump-probe method in both time and spectral domains. Two-photon absorption coefficient enhancement and pump-beam-induced defect mode shift were reported. Both effects are attributed to the light localization in the defect layer of the multilayer structures. Our results demonstrated that defective photonic crystals are good candidates for fabrication of ultrafast all-optical switching devices. © 2006 Optical Society of America.