VUV optical parameters of LiF and color-center formation mechanisms

Abstract

There have recently been considerable advances in tunable lasers based on color centers (CC) in ionic crystals [i]. LiF is one of the most promising crystals for producing CC lasers, as induced emission has already been obtained from F=-, F2J-, and F~-centers. At present, not much is known about many features of CC in LiF, including the CC production mechanisms, the properties of excited CC states, and the mechanisms of CC luminescence excitation. This occurs mainly because it is necessary to use radiation in the relatively inaccessible vacuum ultraviolet (VUV) to examine these features. On the other hand, the use of VUV to produce CC provides direct information on the CC production mechanisms, since it enables one to examine elementary processes in the decay of electronic excitations into Frenkel defects [2].