Crystal field and microscopic spin Hamiltonians approach for V3+ ions in α-ZnAl2S4 single crystals

The optical properties of α-ZnAl₂S₄:V³⁺ single crystals were investigated by S. Angel et al. (Anghel et al., 2011) [1]. The spectra of α-ZnAl₂S₄:V³⁺ reveal electronic transitions between the energy levels of V³⁺ ions located at the octahedral site. A comprehensive theoretical study was performed, examining crystal field, spin-spin and other spin orbit interactions. The calculated energy level schemes significantly correspond with the experimental results of V³⁺ doped α-ZnAl₂S₄ at both low and room temperatures. A novel, consistent interpretation of the radiative properties is proposed, considering the effect of temperature on crystal field parameters. This interpretation supports the potential use of α-ZnAl₂S₄: V³⁺ single crystals, excited at λ_ex = 532 nm, as active media in tunable lasers and amplifiers.