Low Lasing Threshold of MAPbBr₃ Perovskite Quantum Dots Through Manganese Doping

Lead halide perovskite quantum dots (PQDs) have emerged as highly promising materials for low-cost and tunable laser applications due to their exceptional optical properties and solution processability. Doping to PQD introduces a new freedom in controlling their optical properties and structural stability. In this work, we show that Mn-doped MAPbBr₃ QDs exhibit much higher stability in comparison to the pristine QDs. Furthermore, these QDs exhibit a very low lasing threshold at room temperature. This excellent performance is due to Mn²⁺ ions effectively passivating defect states, improving stability, and emission efficiency. The further enhancement of lasing was observed when loaded QDs into Au-coated nanocavities, due to the Purcell effect. Notably, 17% Mn²⁺-doped MAPbBr₃ QDs embedded in nanocavities exhibit a tenfold reduction in lasing threshold compared to undoped samples. These results highlight the synergistic effects of doping and cavity design, providing a pathway toward stable, low-threshold perovskite QD lasers for advanced optoelectronic and photonic applications.