Sub-one-tenth exciton threshold lasers using stable self-charged perovskite quantum rods

While QD charging theoretically reduces the threshold to zero, its effectiveness has been limited by strong Auger recombination and unstable charging. In this study, we theoretically determine the optimal combination of charging number and Auger recombination to minimize the lasing threshold.

Experimentally, we develop stable, self-charged perovskite quantum rods (QRs) as an alternative to QDs via state engineering and Mn-doping strategy. A two-order-of-magnitude reduction in nonradiative Auger recombination enables QRs to support a charging number of up to 6. We then achieve QR liquid lasing with a sub-one-tenth exciton threshold (an average of 0.098 excitons per QR) using 5-nanosecond pulse pumping.