Persistent luminescence found in Mg2+ and Pr3+ co-doped LiNbO3 single crystal

Abstract

Persistent luminescence (PersL) was found in Mg²⁺ and Pr³⁺ co-doped lithium niobate perovskite-like single crystal. Bright red afterglow emission was observed at room temperature for LiNbO₃ excited by a wide range of near ultraviolet light, wherein the defect states associated with Mg²⁺ ions are demonstrated to play an essential role. We propose a charge relaxation mechanism, based on the transition between mid-gap defect states, to describe the PersL phenomenon within the trap–detrap scenario. Given the outstanding ferroelectric, piezoelectric, electro-optical, mechanical, and acoustic-optical properties of the host material, the discovery of PersL in LiNbO₃ opens an opportunity to couple various responses to external stimuli, and thus to develop novel applications based on multifunctional persistent luminescent phosphors (MFPLPs).