
279Crystalline Materials for UV Applications
Chapter 10
the formation of a stable pair of F- and H-centers where the F-center is an anion
vacancy occupied by an electron and the H-center is a
molecule formed by a lat-
tice uorine ion and an interstitial uorine atom. e H-center of the STE can dif-
fuse away from the F-center by thermal activation with activation energy E
a
∼ 0.2 eV
(Mühlig et al. 2010; Rix 2011). e remaining F-center, that is, an electron, is now able
to move within the crystal with a lifetime in the 1000 s range (Lindner 2000). It can be
detected by a typical absorption band at 376nm (Lindner 2000). On a short-time irra ...