Abstract

Each dye molecule embedded in an amorphous material such as a a polymer host experiences a specific molecular environment which strongly influences its electronic transition energies. At low temperatures the different microenvironments result in an inhomogeneously broadened absorption band. The invention of the laser brought new spectroscopic techniques based on energy selection, such as fluorescence line narrowing and spectral hole-burning [1]. These techniques enable convenient addressing of thousands of molecular subsets selected by their transition energy.

© 1991 Optical Society of America