Nonvolatile holographic storage in iron-doped lithium tantalate with continuous-wave laser light

Holograms have been recorded in congruent LiTaO3:Fe with continuous-wave la ser light; by use of a two-step process. Blue gating light (lambda = 488 nm ) sensitizes the crystals for holographic recording with red light (lambda = 660 run) of a diode laser. Refractive-index changes of as much as 1.0 x 1 0(-5) are achieved for intensities of the rea light of 1 W/cm(2). The satur ation values are proportional to the intensity of the writing light. Nondes tructive readout with red light is possible, and the holograms remain erasa ble for blue light. (C) 1999 Optical Society of America. OCIS codes: 210.28 60, 210.4810, 160.5320, 090.2900.