Mechanisms of the dark decay of holograms in LiNbO/sub 3/:Fe crystals

Summary form only given. Two mechanisms of dark decay, proton compensation and electron tunneling have been identified. In LiNbO/sub 3/:Fe with doping levels less than 0.05 wt%, proton compensation dominates the dark decay, while in crystals with doping levels as high as 0.25 wt%, electron tunneling dominates. For crystals with doping levels between 0.05 wt% and 0.25 wt%, both mechanisms contribute significantly to the dark decay, and the single Arrhenius law does not hold anymore with a single activation energy.