MULTIPLEXED STATIC AND DYNAMIC PHOTOREFRACTION IN BI12SIO20 CRYSTALS AT 780-NM

Photorefractive recording of holograms in Bi12SiO20, exhibiting very l ong lifetimes (as great as 3600 s) at near-infrared wavelengths, is re ported. This behavior is observed simultaneously with the principal dy namic recording in the diffusion regime, and no applied electric field is necessary for its observation. The dependence of these long-lived holograms on various recording parameters is studied experimentally. I mage-processing operations such as image addition and subtraction are performed by simultaneous reconstruction of the fast and the slow mult iplexed holograms.