Accumulative recording of nonvolatile photorefractive holograms in LiNbO3 : Fe : Mn crystals

A cyclic scheme of a recording period with a red interference pattern and a n ultraviolet (UV) light and a following post-exposure period with an UV li ght is suggested to accumulate nonvolatile photorefractive holograms in LiN bO3:Fe:Mn with enhanced diffraction efficiency and suppressed scattering no ise. Experimental results as well as an enhancement of diffraction efficien cy up to 30% and a suppression of noise down to near zero are reported. The oretical simulations and corresponding analyses on the optimization of work ing conditions are given, too, No additional equipment is needed in this me thod, and it is of potentials for applications. (C) 2001 Elsevier Science B .V. All rights reserved.