Gated recording based on two-step excitation with metastable shallow traps is analyzed theoretically. A two-center model, including the tail of the conduction band into the bandgap, is suggested. The tail provides a way to model efficiently excitation from deep to shallow traps and long recombination times back into deep traps. The results are compared with experimental results performed with La3Ga5SiO14, and good agreement is found. Further, the limiting material parameters determining the material sensitivity are identified.
© 2001 Optical Society of America
Thomas Nikolajsen, Per Michael Johansen, Boris I. Sturman, and Evgeni V. Podivilov, "Modeling of photorefractive two-step gated recording by long-life-time intermediate levels," J. Opt. Soc. Am. B 18, 485-491 (2001)