title: Spin-lattice relaxation in the excited (4)S(3/2) state of Er(3+) in LaF(3).
abstract: We have employed a purely optical method to measure spin-lattice relaxation in the lower excited (4)S(3/2) state of Er(3+) in LaF(3) at helium temperatures. Above 3 K the relaxation is dominated by an Orbach process through the upper (4)S(3/2) state. Below 3 K the relaxation is caused by some residual mechanism that obscures the Kramers-Van Vleck direct process. By relating the Orbach relaxation measurements to the homogeneous broadening of the upper (4)S(3/2) level, we determine values of the transition rates between the upper and lower (4)S(3/2) states.
authors.forename: M M
authors.initials: MM
authors.lastname: Broer
authors.forename: J
authors.initials: J
authors.lastname: Hegarty
authors.forename: G F
authors.initials: GF
authors.lastname: Imbusch
authors.forename: W M
authors.initials: WM
authors.lastname: Yen