title: Converting Eu3+ between defect sites in BaFCl for persistent spectral hole burning.
abstract: Persistent spectral hole burning (PSHB) is demonstrated in the (7)F(0)-->(5)D(0) optical transition of Eu(3+) doped into crystals of BaFCl. For Eu(3+) ions at two different lattice sites, persistent holes can be burned at temperatures below 77 K. The characteristics of the hole-burning process suggest that the observed PSHB effect is due to laser-excitation-induced site-to-site conversion. One type of Eu(3+) site is converted into another type of defect site. This process is not optically reversible, and holes can be erased only when the temperature increases to 150 K.
authors: Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
authors: S T
authors: ST
authors: Li
authors: G K
authors: GK
authors: Liu
authors: W
authors: W
authors: Zhao