Persistent spectral hole burning studies of F2 color center in lithium fluoride

Color centers were produced in lithium fluoride (LiF) single crystal by gamma rays. Low-resolution transmission and emission measurements of LiF revealed several zero-phonon transitions. High-resolution excitation spectrum revealed three closely spaced zero-phonon lines at 601 nm belonging to different sites. F2 center is the dominant site. Optical hole burning studies were performed in all these sites. Hole kinetics are performed as a function of temperature, laser power and time. We have demonstrated experimentally the production of light-induced centers.