Experimental studies of spontaneous emission from dopants in an absorbing dielectric

Abstract

We report the first measurements, to our knowledge, of the modification of spontaneous emission rates of Eu³⁺ ions in the visible region owing to an absorbing medium. Precise levels of the absorption coefficient are introduced by codoping with different amounts of Nd³⁺. We use a binary glass system PbO-B₂O₃ as the host, the compositional variation of which leads to a change in the real part of the refractive index. Measured lifetimes are found to follow the real cavity model, and the data are analyzed by the model proposed by Scheel et al. [Phys. Rev. A 60, 4094 (1999)]. We give estimates of the parameter that is related to the radius of the cavity around Eu³⁺.