Lens-Like Effect in LiNbO₃ : Fe Photorefractive Crystal

The lens-like effects, both photorefractive effect and thermo-optical effect, were studied in the LiNbO₃ : Fe sheet. The threshold light intensity above which the photorefractive effect was overwhelmed b-v the thermal effect was determined and the thermo-optical coefficient dn/dT is evaluated by the Z-scanning method. The limiting characteristics of LiNbO₃ : Fe sheet is examined.