Molecular electronics for frequency domain optical storage: Persistent spectral hole-burning - A review

Abstract : Persistent spectral hole-burning (PHB) is a phenomenon that allows an additional dimension, the frequency at which spectral holes are written, to be used to encode digital data. PHB can be used to store a large number of bits of information in the volume irradiated by a focused laser beam, leading to a possible future storage technology, frequency domain optical storage. A large number of photochemical and photophysical mechanisms have led to the production of spectral holes; a wealth of information has been learned about host-guest interactions, dephasing, and solid-state photochemistry at low temperatures. The general structure of a frequency domain optical store places a set of constraints on the engineering of such a system as well as on the materials used as recording media. The dynamics of the hole-burning process are crucial; for monophotonic mechanisms in particular, a set of stringent constraints can be derived that limit the applicability of this class of materials. Recent discoveries of two-color, photon-gated hole-burning offer special promise for nondestructive reading and improved performance.