Hologram multiplexing using two-step recording
We present a comparison of different two-step holographic recording schemes based on their multiplexing performance using a unified framework. The difference between the different schemes is mainly due to the energy levels and sources of the traps. The influence of effective trap density and recording and sensitizing intensities are addressed. It is shown that for low light intensity operation, the performance of the doubly-doped crystals is superior due to the lack of dark depopulation of the shallow traps. Usage of such crystals also results in the suppression of the intensity threshold that exists for two-step recording in singly-doped crystals. The promising potentials for improvements in the two-step holographic recording in doubly-doped materials is also addressed.