Low Temperature Optical Dephasing of Rare Earth Ions by Tunneling Systems in Glass

Abstract

Optical dephasing of paramagnetic ions and molecules in organic and inorganic amorphous solids at low temperatures (≲100K) is characterized by unusual temperature dependences and enhanced relaxation rates compared to crystalline systems1. For a large variety of impurity-host combinations the dephasing rate has been found to follow a Tm temperature dependence with m approximately 2. Several theories have attempted to explain this behavior by assuming interactions between the optical center, phonons, and atomic tunneling systems. However, the role of the intrinsic disorder in optical dephasing in these systems is not clearly understood.