Abstract
One-color two-photon excitation spectra of the and transitions of in have been measured at low temperature and their dependences upon photon polarization analyzed. Linewidths on the order of 0.2, 0.6, and 1.0 are obtained for the (), (), and () Stark components observed at 15 K, respectively. The () transition is observed to be isotropic within experimental error, while the and components of the transition exhibit the anisotropic patterns expected in symmetry. Calculations of two-photon transition intensities are conducted within the framework of the phenomenological model previously used for in MClF (M=Ba,Sr) and in , where the rare-earth ion occupies sites of and symmetries, respectively. The present results are compared and contrasted with those obtained in these previous cases.
- Received 14 September 1992
DOI:https://doi.org/10.1103/PhysRevB.47.11712
©1993 American Physical Society