OPTICAL SPECTROSCOPY OF SINGLE IMPURITY MOLECULES IN SOLIDS

Optical spectroscopy of a single impurity molecule provides the first truly local probe of host-guest interactions in doped solids. In conventional optical high-resolution experiments with many molecules only ensemble averages of the microscopic parameters can be obtained. In the single-molecule regime, the exquisite sensitivity of an individual dopant molecule to both the local environment and to external perturbations has been exploited in recent experiments to reveal a wealth of fascinating novel phenomena such as spectral diffusion in crystals and polymers, optical modification of a single impurity molecule (spectral hole-burning), local field measurements at the site of a single impurity molecule, and quantum optics in a solid.