Two-color plane-wave holography in reduced, near-stoichiometric lithium niobate

Two-color, or photon-gated, holographic recording materials show promise for applications such as optical data storage where nondestructive readout is required. In this paper, the growth and decay of plane-wave holograms as a function of the degree of reduction for a crystal of LiNbO3 with a composition close to stoichiometric are studied. The photorefractive sensitivity of for the two-color recording at 852 nm, gates at 488 nm is approximately 30,000 times higher than of fully oxidized congruent material for writing and gating intensities of 1 W/1 cm2. Gating with shorter-wavelength light would increase this sensitivity still further.