Nonvolatile two-color holography in Mn-doped near-stoichiometric lithium niobate

Nonvolatile holograms are recorded in near-stoichiometric LiNbO3 doped with 8 ppm of Mn by use of a two-color holographic recording method. An IR laser with wavelength of 778 nm is used for writing and a UV laser with wavelength of 350 nm is used for gating. Dependences of two-color sensitivity and M/♯ on gating and writing intensities are presented. Significant improvements of sensitivity, M/♯, and dark decay are obtained compared with reduced near-stoichiometric LiNbO3. The obtained high two-color sensitivity of 0.21 cm/J with a gating intensity of 1.5 W/cm2 is attributed to large light-induced absorption of small polarons.