Abstract

A microscopic model of a chromophore embedded in a glassy matrix, and interacting with phonons and two level systems (TLS) will be presented. The hamiltonian contains a a thermal (quantum) bath of phonons, chromophore (with a vibrational mode) interacting with phonons, and two level systems interacting with phonons. By a transformation of this hamiltonian, the linear chromophore-phonon and TLS-phonon interactions can be removed, leading to a new hamiltonian with TLS-chromophore interactions, TLS-TLS interactions, and residual phonon-TLS coupling. These terms produce TLS flips and dephasing and are often used as the starting point for spectral diffusion models of dynamics.

© 1992 Optical Society of America