Optical spectroscopy of BaY₂F₈:Dy³⁺

Abstract

The optical spectra of the BaY2F8:Dy3+ laser crystal have been investigated in the 5000–30 000 cm−1 range. The Judd–Ofelt parametrization scheme has been applied to the analysis of the room temperature absorption spectra. The calculated radiative lifetime of the 4F9/2 state is 1.48 ms. Decay curves of the visible emission have been measured as a function of the temperature for two different Dy3+ concentrations (0.5 and 4.4%). In the case of the diluted crystal the emission profiles are single exponential with decay times consistent with the radiative lifetime. The decay curves of the concentrated crystal are not exponential and they obey the Inokuti–Hirayama model for energy transfer for an electric dipole–dipole interaction in the absence of diffusion among the donors. The emission cross section at 575 nm has been estimated using the integral β–τ method in order to assess the potentialities of this compound as a solid state laser material in the yellow region.

Optical spectra of Dy3+ in KY3F10 and LiLuF4 crystalline fibers

“…4). It has to be observed that in most cases the decay time of the 4 F 9/2 emitting level of Dy 3+ -doped materials slightly increases with the temperature [8,17,22]. Kaminskii et al [17] ascribe this behavior to the fact that some approximations intrinsic of the Judd-Ofelt approach are not fulfilled in practice, in particular those affirming on one hand that the population of the Stark levels of the initial manifold of a J-J 0 channel should be the same, and on the other that the probabilities of all inter-Stark electric dipole transitions should be equal.…”

“…To date, fluorides have been investigated as host materials for the dysprosium ion mainly to develop NIR laser rather than visible-emitting media [7]. Nevertheless, in a paper concerning Dy 3+ in BaY 2 F 8 (BYF), we have evidenced some interesting peculiarities with respect to the more extensively investigated oxide lattices [8]. For this reason, we have decided to extend our studies to other fluorides, and in this paper we present results obtained for Dy 3+ -doped KY 3 F 10 (KYF) and LiLuF 4 (LiLuF) crystalline fibers.…”

Luminescent properties of ZrO2:Dy3+ and ZrO2:Dy3++Li+ films synthesized by an ultrasonic spray pyrolysis technique

“…Due to the cross relaxations, Dy 3 þ ions at the 4 F 9/2 multiplet can be de-excited to the 6 H 9/2 ( 6 F 11/2 ), 6 H 5/2 , or 6 F 1/2 multiplet, in the mean-while Dy 3 þ ions at the ground state 6 H 15/2 are excited to the 6 F 3/2 , 6 F 7/2 or 6 H 9/2 ( 6 F 11/2 ) multiplet. Then, all the Dy 3 þ ions concerned in the cross relaxations relax to the ground state non-radiatively, as a consequence the emissions associated to the 4 F 9/2 multiplet are quenched, in according to reference [33]. The ZrO 2 :Dy 3 þ films have outstanding PL luminescent emissions, which can be appreciated at simple sight, with a normal room light, when they are excited with an ultraviolet lamp (254 nm).…”

The optical properties of Dy3+-doped NaY(MoO4)2 crystal

“…2 and the maximum emission cross-sections are 1.14 Â 10 À20 and 1.21 Â 10 À20 cm 2 for the p and s polarization at 575 nm, respectively. For comparison, the emission cross-sections of Dy 3+ :YAl 3 (BO 3 ) 4 at 574 nm for p and s spectra were found to be 1.04 Â 10 À20 and 1.27 Â 10 À20 cm 2 , respectively [20], and of Dy 3+ :BaY 2 F 8 at 574 nm was found to be 0.32 Â 10 À20 cm 2 [21]. However, it should be noted that the values calculated depend on incertitude of several parameters.…”