Spectroscopy of rare earth ions in insulating materials

摘要

This paper briefly reviews some of the spectroscopical results obtained for the Eu$+2$PLU$/ and Ce$+3$PLU$/ ions in the cubic perovskite KMgF$-3$/. Both linear and non-linear spectroscopic techniques have been employed to assess the role played by the crystal-field and the lattice dynamics in modifying the optical properties of these rare-earth ions.