Abstract

Optimistic estimates put the limits for PSHB storage up to 10¹² bits per cm² (i.e. 10⁴ spectral holes per each diffraction limited surface pixel of the size of λ·λ=10^-8 cm², λ- wavelength) or 10¹⁶ bits per cm³ for a volume storage memory (cell size λ·λ·λ=10¹² cm³). Energy transfer between impurities destroys the storage. Interaction is absent at low concentrations, however, the latter may result in critical decrease of the number of impurity moleculess available to burn a hole at a fixed wavelength at a fixed spatial spot. If we assume concentration of non-interacting impurities 10¹⁸ molecules per cm³, and the storage density of 10¹² bits per cm² or 10¹⁶ bits per cm³, there is only 100 molecules on average to store one bit of information. It is a too small amount because of the fluctuations of the number of molecules per cell [1,2] and references therein.

© 1992 Optical Society of America