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).