Effects of halides on luminescence behaviors of Ce3+ ions in chalcohalide glasses

We report photoluminescence of Ce3+ ions in GeS2-Ga2S3-CsH (H = Cl, Br, I) chalcohalide glasses. Halides exert a major effect on luminescence behaviors of Ce3+ center in chalcohalide glasses with respect to both intensity and wavelength. In particular, the Ce3+ doped chalcohalide glass containing CsBr exhibits an intense broad emission in the green-yellow region which is much enhanced and experiences an obvious blue shift with the increase of the CsBr content. The origin of these unique luminescence behaviors is discussed in detail according to the formation of [GaS3/2Br]− structural units and the optical basicity theory. The former reduces the phonon energy of glass matrix, thus increasing the luminescence efficiency, while the latter explains well the sensitivity of Ce3+ emission to the environment where Ce3+ ions locate.