Abstract
The reorientation efficiency of M centers in CaF2 is found to be directly proportional to the M+ center concentration. The wavelength dependence of the efficiency for optically induced reorientation is also found to agree with the M absorption rather than the MF. We propose that the M centers in CaF2 reorient under ultraviolet excitation by first photoionizing, i.e., becoming an M+ center; this M+ center then absorbs light in the same spectral range and reorients during a nonradiative transition from the excited state. This agrees with the mechanism found previously in the alkali halides.

This publication has 7 references indexed in Scilit: