Influence of the photovoltaic effect on optical limiting with lithium niobate

Optical limiting and speckle of low power continuous wave laser beams using nonlinear scattering in photorefractive Zr: LiNbO3 crystals

“…Over the past few years there has been a considerable interest in optical limiting (OL) of low power continuous wave (CW) laser beams using photorefractive (PR) materials [1,2]. Recently, iron-doped lithium niobate (Fe:LiNbO 3 ) has emerged as a very efficient optical limiter, producing changes in optical density (DOD) of up to 4 with l/e and switching speeds of a few milliseconds in a simple focal plane geometry [2]. The origin of the large DOD is an exceptionally high optical gain coefficient, which was reported to be as high as 100 cm À1 [2].…”

“…Recently, iron-doped lithium niobate (Fe:LiNbO 3 ) has emerged as a very efficient optical limiter, producing changes in optical density (DOD) of up to 4 with l/e and switching speeds of a few milliseconds in a simple focal plane geometry [2]. The origin of the large DOD is an exceptionally high optical gain coefficient, which was reported to be as high as 100 cm À1 [2].…”

“…The OL devices rely on one or more of the nonlinear optical mechanisms, which include excited saturation absorption (ESA), two-photon absorption (TPA), nonlinear refraction, nonlinear scattering (NLS), and PR self-defocusing [1][2][3][4][5]. NLS is a wellknown phenomenon leading to OL in various media with nanoparticles [6,7].…”