Inhomogeneous broadening of electron-paramagnetic-resonance and optical spectra ofV4+inCaYAlO4

Abstract

CaYA104 crystals codoped with V + and Mg + ions have been grown in an inert atmosphere. EPR measurements reveal that V + ions in CaYA104 occupy orthorhombic symmetry sites. The optical-absorption spectrum comprises two intense bands with peaks at 330 and 430 nm, together with a weak band around 500 nm. Excitation in the 500-nm band produces a broad luminescence band with a peak at 690 nm. The radiative center associated with these spectra is assigned to V +(3d ) ions. The peak wavelength of the luminescence band shifts to longer wavelengths with increasing excitation wavelengths in the 500-nm absorption band, an efFect associated with the inhomogeneous broadening of the luminescence band caused by random distribution of Ca + and Y + ions in the disordered CaYA104 lattice.

Determination of the oxidation state and coordination of a vanadium doped chalcogenide glass

“…Vanadium 4+ doped CaYAlO 4 displays a broad absorption band at 500 nm [30]. Two excitation peaks for V 4+ have been observed due to the Jan-Teller effect at 427 and 490 nm in Al 2 O 3 , at 419 and 486 nm in YAlO 3 and at 432 and 500 nm in yttrium aluminium garnet (YAG) [29].…”

Analysis on the local structures for 3d1 impurities (Ti3+ and V4+) in KTiPO4

“…Thus, the relatively smaller D q (≈490 cm −1 ) and higher covalency factor N (≈0.95) may be expected for the Ti 3+ centre C 1 in KTP. In light of the optical absorption studies for V 4+ in oxides, [33] the spectral parameters D q (≈2300 and 2500 cm −1 ) and N (≈0.91 and 0.9) can be estimated for the V 4+ centres C 2 and C 3 , respectively, in consideration of the slight difference in R. Third, the normalization factors N γ and the orbital admixture coefficients λ t , λ e , and λ s are computed by using the CA [8,9] and listed in Table 1. With the quantities ζ d 0 ≈ 154 and 248 cm −1 [34] and P 0 ≈ − 0.00256 and 0.0172 cm −1 [35] for free Ti 3+ and V 4+ , and ζ p 0 ≈ 151 cm −1 for free O 2-, [36] respectively, the spin-orbit coupling coefficients ζ and ζ', the orbital reduction factors k and k' and the dipolar hyperfine structure parameters P and P′ are given in Table 1.…”

STUDIES OF THE LOCAL STRUCTURE AND THE g FACTORS FOR THE ORTHORHOMBICTi3+CENTER IN YAP

“…[6][7][8] To investigate the energy levels and electronic properties, which are closely related to the laser behaviors of doped YAP, systematic and interesting electron paramagnetic resonance (EPR) studies have been carried out on this material with some transition-metal dopants (e.g., Ti 3+ , V 4+ , Cr 3+ ). [9][10][11][12][13] For example, the orthorhombic Ti 3+ center with the optical absorption band centered at 434 nm (band A) and 492 nm (band B) were observed, and the anisotropic g factors g x , g y and g z were also measured. 10 This center was assigned to Ti 3+ located on the orthorhombic Al 3+ site.…”