Pressure Coupled Lanthanide Ion Doping to Enhance Optical Properties in BaTiO 3 .

Self-trapped excitons (STEs) typically give broadband photoluminescence emission with a large Stokes shift, which is important for the enhancement of the optical properties of materials. Here, low-dimensional La-doped BaTiO 3 nanocrystals with defects are prepared using supercritical CO 2 (SC CO 2 ). The generation of the STEs is facilitated by doping La 3+ ions and introducing CO 2 pressure, which effectively enhance the luminescence intensity of BaTiO 3 . This discovery shows that the La ion doping concentration can modulate the photoluminescence of BaTiO 3 nanocrystals under pressure. This work deepens the understanding of the influence of rare-earth-doped luminescent materials under pressure and provides insight to improve the capabilities of optical devices.