Picosecond Dynamic Nonlinear Optical Processes in Semiconductors.

Available from UMI in association with The British Library. Picosecond pump-probe and transient grating experiments were performed at 1.64 μm on an In_{0.53}Ga_ {0.47}As-InP sample. Conditions for cw optical bistability in both thermal-vacuum-deposited and molecular-beam-grown ZnSe -based nonlinear interference filters are experimentally and theoretically explored, at He-Ne (633 nm), Kr (647 nm) and Ar-ion (514 nm) wavelengths. Theoretical analysis also demonstrates that observed drift instabilities in the nonlinear response of ZnSe-based nonlinear interference filters correlate well with the highest internal irradiance levels. Nanosecond switch-ON of optical bistability in thermal-vacuum-deposited ZnSe-based nonlinear interference filters was observed. Switching is caused by ~15 psec (HW 1/e M), 532 nm pulses and is monitored by the transmission of cw He-Ne laser radiation. Nanosecond switch-OFF is also achieved, for a molecular-beam-grown sample. In both cases the driving mechanism is consistent with a fast induced thermal refractive index change. Wavelength -insensitive and angle-insensitive switching is also demonstrated for a filter with a thin aluminium coating.