Picosecond optical limiting in reverse saturable absorbers: a theoretical and experimental study
Abbreviated Journal Title
J. Opt. Soc. Am. B-Opt. Phys.
EXCITED-STATE ABSORPTION; NONLINEAR ABSORPTION; ORGANIC-DYES; Z-SCAN; POLYMETHINE; LIMITERS; PULSE; Optics
We theoretically and experimentally study absorption of picosecond laser pulses in materials described by a four-level system that exhibit reverse saturable absorption (RSA). Using an approximate solution to the rate equations, we derive, analyze, and verify, numerically and experimentally, a single dynamical equation for the spatial evolution of the pulse fluence that includes both the rate equations and the propagation equation. This analytical approach considerably simplifies the study of optical limiting with picosecond pulses and helps to predict the behavior of the nonlinear transmittance, the level of output signal clamping, and a possible turnover from RSA to saturable absorption that restricts the performance of optical limiters based on RSA. The results obtained can also be used to characterize RSA materials by the pump-probe technique. (C) 2002 Optical Society of America.
Journal of the Optical Society of America B-Optical Physics
"Picosecond optical limiting in reverse saturable absorbers: a theoretical and experimental study" (2002). Faculty Bibliography 2000s. 3313.