Hole-Burning Memories: A Frequency Selective Mesoscopic Approach to Molecular Storage

Abstract

Due to the long wavelength of visible light, most straight forward optical methods, like absorption or emission spectroscopy, are not well suited for spectroscopy on a “molecular level”. The hole-burning method is a selective spectroscopy scheme based on energy selection. This method yields, at low temperatures, very high spectral resolution and, hence, can be used to investigate molecular environments and molecular potentials. With the simultaneous application of external fields the hole-burning technique is a true two-dimensional spectroscopy method. Hole-burning can also be used for enhancing the schemes of presently used optical memories by many orders of magnitude. In this context new developments based on the use of semiconductor laser diodes are reported. The question of the requirement of low temperatures is also critically reviewed and, finally, a comparison between mesoscopic storage schemes and molecular schemes is given.