The photo-Hall technique has been used to investigate the properties of the InSb optical absorption band-edge. An accurate theoretical explanation of the linear absorption results is given, together with new data on the nonlinear aspects of the band-tail. A value of 1.1 x 10-18 for a has been calculated by monitoring the carrier generation during bistability.

The nonlinear absorption coefficient of As(2)S(3) glass has been measured to be 2.0 cm/GW for femtosecond pulses at 800 nm. Femtosecond laser structuring via two photon absorption in bulk As(2)S(3) glass by erasable and permanent photo-darkening is demonstrated using both holographic and direct multi-beam laser writing.

This paper studies the terahertz optical properties of nonlinear potassium titanyl phosphate crystals with different conductivities in the spectral range of 0.2 to 2.6 THz. The observed properties are characterized by several absorption lines lying along different optical axes which represent the relevant potassium sublattice phonon modes. The peculiarities of these absorption lines are attribu...

Two novel optical power limiters, 2-[ethyl-(4-phenylazo-phenyl)-amino]-ethanol (E4PA) and 2-[ethyl-(4-trifluoromethyl-phenylazo-phenyl)-amino]-ethanol (E4TPA) were synthesized using a diazotization reaction. The purified azo material was made into thin films in a poly(methyl methacrylate) matrix using a gravity settling technique. The electronic nonlinearities of these films were investigated u...