Optical properties of Sr1−xEuxGa2S4 mixed compounds Original Research Article

The mixed crystal system of CaGa2S4–EuGa2S4 has already been investigated and confirmed to form the solid solution. In this report, the same procedure of the previous report is applied to the SrGa2S4–EuGa2S4 system using differential thermal analysis and X-ray diffraction. It is shown that the solid solution is also formed in this system. Photoluminescence spectra of the present system have a broad-wavelength peak characteristic of the phonon-terminated 5d–4f transitions. The peak energy of the emission shifts to the low-energy side as x increases. The maximum intensity of the emission is attained at 10 mol% as about four times larger in magnitude than the emission of a stoichiometric EuGa2S4 compound.