Growth and optical properties of Eu2+/Li+-co-doped SrB4O7 single crystals

This paper reports the growth and optical properties of Eu2+/Li+-co-doped SrB4O7 single crystals. High-quality Eu,Li:SrB4O7 crystals without macro-defects or cracks were grown using the top-seeded solution growth (TSSG) method. The absorption and luminescent properties were measured and different spectra were observed in the as-grown crystals. As the doping amount of lithium increases, the absorption peak at 300 nm becomes stronger and the emission peak shifts to a longer wavelength. This phenomenon could be attributed to the doping lithium ions, which might affect the electric field distribution in the lattice structure.

Research highlights
► We investigate the growth of high-quality big Eu,Li:SBO crystals.
► Eu3+ can be reduced to Eu2+ in the growth of Eu,Li:SBO crystals.
► Doped lithium ions have an effect on optical properties of Eu2+ in the Eu,Li:SBO crystals.