Nonvolatile holographic storage in lithium tantalate with a two-step process using continuous-wave laser light

Summary form only given. We have examined congruent LiTaO/sub 3/:Fe crystals which were reduced by annealing in vacuum. Holograms are recorded with either a 660 nm or a 785 nm laser diode (30 mW) and light of an Ar+ laser serves as sensitising light (488 nm). The two recording beams have equal intensity and are extraordinarily polarized. LiTaO/sub 3/:Fe is insensitive for holographic recording with red writing light alone. Nevertheless, recording becomes possible, if the crystal is sensitized with additional blue light.