Abstract

Although photoionization of divalent and trivalent rare earth ions in ionic crystals has been an intensive field of research in the last decades (see Ref. 1 and references therein), the nature of the electron traps remains ununderstood in many cases. As applications like photoionization hole burning for frequency-domain optical memories require a high density of stable electron traps other than the ionized species, the need for a characterization of the trapping dynamics is evident.

© 1997 Optical Society of America