Phosphors usable for the construction of solid-state lasers

As an entirely new and interesting option for the construction of solid-state lasers, we have begun to investigate the optical and vibrational properties of KLuS₂-based ternary sulphides doped with Tm³⁺ and Yb³⁺ ions, known for their infrared emission. The measured Raman spectra showed that the KLuS₂ matrix has a very low phonon energy (E_ph ~ 220 cm^-1), which results in certain emission transitions (some of the 4f → 4f Tm³⁺ transition) observed in the emission spectra, which are inaccessible in the matrices with higher phonons energy. This makes these ternary sulphides suitable candidates for the construction of solid-state lasers in infrared spectral range.