[Optical limiting response in Er3+-doped TeO2-Nb2O5-ZnO glass]

Nonlinear optical properties of Er+ doped heavy metal telluride glass were studied by picosecond laser pulses. The optical limiting response was measured by a transmission technique, and the reverse saturable absorption (RSA) by a Z-scan technique. When the incident power reached the threshold, the tranmitted power did not grow rapidly with the incident power as before, but remained almost constant. It means that the Er3+ -doped glass possesses an optical limiting effect. The experimental results show that the excited absorption is responsible for the measured RSA, resulting in optical limiting response. The measured data can be well simulated by a rate equation model to obtain the absorption cross sections of the excited state.