Growth and Spectroscopic Properties of Pr3+ Doped Lu2S3 Single Crystals

For the first time Lu$_2$S$_3$ (undoped and Pr-doped) single crystals were successfully grown from melt using micro-pulling-down (mPD) technique. Customization of halide mPD apparatus allowed us to grow rod-shaped (\O 2 mm and length around 20 mm) crystals of Lu$_2$S$_3$ with high melting temperature (~1750 $^\circ$C). X-ray powder diffraction revealed that the grown crystals exhibit the {\epsilon}-Lu$_2$S$_3$ crystal structure ($\alpha$-Al$_2$O$_3$ type, space group R-3c). Optical and scintillation properties of both the undoped and Pr$^{3+}$ doped Lu$_2$S$_3$ were investigated. Fast 5d-4f Pr$^{3+}$ luminescence was observed in both photoluminescence and radioluminescence spectra. The presented technology is an effective tool for the exploration of a large family of high-melting sulfides. Such materials show promise for application as scintillators, active laser media, and optoelectronic components.