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The steady-state light-induced absorption and the temporal relaxation behavior under illumination of cw ultraviolet light in Mn-doped near-stoichiometric LiNbO3 with different crystal compositions are investigated. The ultraviolet-light-induced absorption has been assigned to small polarons NbLi4+ by measuring the absorption spectra at room temperature. The dependences of relaxation behaviors (time constant and stretching factor) of light-induced absorption on various illumination conditions (intensity, polarization) and temperature are presented, which are very different from those observed in Fe-doped LiNbO3 illuminated with highly intense light pulse, though the temporal relaxation follows the same stretched-exponential decay behavior in both cases. The results are explained reasonably by using the model of distance-dependent electron transition probabilities between localized deep traps and small polarons without any additional assumptions, and discussed to tailor doped near-stoichiometric LiNbO3 crystals for two-color holographic recording with cw laser light. [ABSTRACT FROM AUTHOR]

Near-stoichiometric LiNbO3 crystals slightly doped with Mn from melts with different compositions are grown by the top seeded solution growth method. The growth parameters such as temperature field, pulling, and rotation rates are optimized. Two-color holograms are recorded in these crystals by the use of a near infrared laser of 778 nm for writing and an ultraviolet laser of 350 nm for gating. The light-induced absorption changes and two-color holographic characteristic performances are presented and compared. The results show that crystals with composition closer to stoichiometry exhibit better two-color holographic storage performance. [ABSTRACT FROM AUTHOR]

The steady-state light-induced absorption and the temporal relaxation behavior under illumination of continuous wave ultraviolet light in Mn-doped near-stoichiometric LiNbO3 with different crystal compositions are investigated. The ultraviolet-light-induced absorption is assigned to small portions Nb(super 4+)(sub Li) by measuring the absorption spectra at room temperature.

The steady-state light-induced absorption and the temporal relaxation behavior under illumination of cw ultraviolet light in Mn-doped near-stoichiometric LiNbO3 with different crystal compositions are investigated. The ultraviolet-light-induced absorption has been assigned to small polarons NbLi4+ by measuring the absorption spectra at room temperature. The dependences of relaxation behaviors (time constant and stretching factor) of light-induced absorption on various illumination conditions (intensity, polarization) and temperature are presented, which are very different from those observed in Fe-doped LiNbO3 illuminated with highly intense light pulse, though the temporal relaxation follows the same stretched-exponential decay behavior in both cases. The results are explained reasonably by using the model of distance-dependent electron transition probabilities between localized deep traps and small polarons without any additional assumptions, and discussed to tailor doped near-stoichiometric LiNbO3 crystals for two-color holographic recording with cw laser light. [ABSTRACT FROM AUTHOR]