Time-resolved spectral holeburning in LaF₃:Ho³⁺ and YLiF₄:Er³⁺

We have used delayed optical free induction decay and time resolved holeburning with microsecond resolution to investigate spectral diffusion in LaF3+ and YLiF4+ at 1.4 K. The magnetic moments of the rare earth ions strongly perturb the nuclear spins of neighboring fluorine ions, resulting in a distribution of fluorine flip rates. Spectral diffusion arises from the coupling of the rare earth centers to the fluorine nuclear magnetic moments. Increases in holewidth of up to two orders of magnitude were observed between 1 μs and 10 ms. © 1990.