Transient differential absorption spectra of solgel glasses that contain copper selenide nanoparticles (NP’s) have been studied with a picosecond pump–probe technique. Oxidation of copper selenide NP’s results in the appearance of an additional absorption band peaked at ∼1 μm, which can be transiently bleached under laser excitation. Excited-state absorption related to mid-gap surface trap states was observed. The absorption recovery time was found to be ∼300 ps. The intensity-dependent transmission of oxidized copper selenide NP’s in solgel glass at 1.08 μm has been measured. Permanent laser-induced absorption changes in the glasses were studied with nanosecond pulses as a function of laser exposure. Passive Q switching of 1.06-μm Nd3+:Y3Al5O12, 1.34-μm Nd3+:YAlO3, and 1.54-μm Er3+: glass lasers has been realized with the glasses containing copper selenide NP’s used as saturable absorbers. Q-switched pulses with 100-ns (1.06 μm), 90-ns (1.34 μm), and 60-ns (1.54 μm) pulse widths were obtained.
© 2000 Optical Society of America
[Optical Society of America ]
K. V. Yumashev, N. N. Posnov, I. A. Denisov, P. V. Prokoshin, V. P. Mikhailov, V. S. Gurin, V. B. Prokopenko, and A. A. Alexeenko, "Nonlinear optical properties of solgel-derived glasses doped with copper selenide nanoparticles," J. Opt. Soc. Am. B 17, 572-579 (2000)