Temperature dependence of laser-induced fluorescence of Tb3+ in molten LiCl-KCl eutectic

► A cross-relaxation energy effect of Tb3+ in high temperature molten salt. ► Fluorescence spectra and lifetimes originated from both 5D3→7FJ and 5D4→7FJ transitions of Tb3+. ► The cross-relaxation effect becomes weakened with increasing temperature.