Optical spectroscopy and crystal-field analysis of YAl₃(BO₃)₄single crystals doped with dysprosium

Abstract

YAl3 (BO3)4 crystals doped with Dy3+ were grown from a potassium trimolybdate flux. Their absorption and visible emission spectra and decay curves were measured at temperatures ranging from 10 to 298 K. The complete energy level scheme has been deduced from the low temperature measurements and reproduced by theoretical calculations based on a parametric Hamiltonian including coulombic, spin–orbit and crystal-field terms. The Judd–Ofelt parametrization scheme has been applied to the analysis of the room temperature absorption spectra. The calculated radiative lifetime of the 4F 9/2 state is 344 μs; this value is reasonably consistent with the experimental data.

Crystal-field analysis of Er3+ ions in yttrium aluminium borate (YAB) single crystals

“…These values are in good agreement with those reported for Er 3+ ions in other host [12,[17][18][19]. The Er 3+ free-ion parameters are also compared in Table 3 with those of Dy 3+ in the same host [16]. Considering only the contribution of the first coordination sphere around the Ln 3+ ion, this coordination sphere is composed of six equivalent O 2− ligands.…”

“…It has been found that the fourth and sixth order CF parameters strongly differ from the corresponding ones in the best-fit set. This has been previously obtained for the two lanthanides Nd 3+ [15] and Dy 3+ [16] in the same host. This disagreement between the starting values and the final fit values was explicated by the contribution of the second coordination sphere around the Ln 3+ ion [16].…”

“…For this comparison, the use of the crystal-field strength parameters is more reasonable approach. These crystal-field strength parameters Table 4 Crystal-field strength parameters for Nd 3+ , Dy 3+ and Er 3+ in YAB Nd 3+ [15] Dy 3+ [16] Er 3+ (this work) are defined by [23,24]:…”

“…The crystal-field strength parameters of Dy 3+ (4f 9 ) [16], and Nd 3+ (4f 3 ) [15] in YAB are shown in Table 4 in comparison with those of Er 3+( 4f 11 ) in the same host. There is a general similarity between the strength parameters of the three compounds.…”

Optical spectroscopy of NaLa(WO4)2:Dy3+ single crystal

“…Moreover, Dy 3+ -doped garnets have been indicated as potential saturable absorbers in the 2.8 m region [3]. As a consequence, the interest in the optical properties of Dy 3+ -doped oxides is considerably increasing currently [4][5][6][7][8].…”