Multiplexing and M# measurement in spectral hole burning medium

Summary form only given Spectral hole burning holography can store both the temporal and spatial information. In cryogenic temperature, only a certain group of atoms in the spectral hole burning material can interact with the incident photons of specific frequency. It allows an extra degree of freedom to store and access information, i.e. the frequency domain. 12,000 holograms at a single location by frequency multiplexing has been demonstrated. The storage capacity can be further increased by combining angle and frequency multiplexing. A system measure of the hologram diffraction efficiency obtainable by multiplexing M holograms at a single location and frequency is given by the M/#. In the paper we report the measurement of M/# in a 400 /spl mu/m thick sample of H/sub 2/TBNP in polyvinyl butyral (PVB) with a concentration of 3 /spl times/ 10/sup -5/ mol/l.