Stable self-charged perovskite quantum rods for liquid laser with near-zero threshold

TL;DR

This paper presents the development of stable, self-charged perovskite quantum rods that achieve near-zero lasing threshold in liquid lasers by significantly reducing Auger recombination and enabling high charging states.

Contribution

The study introduces a novel Mn-doping strategy to create stable self-charged perovskite quantum rods with ultra-low lasing thresholds, surpassing previous QD laser performance.

Findings

Achieved a near-zero lasing threshold of 0.098 with quantum rods.

Reduced nonradiative Auger recombination by two orders of magnitude.

Supported a charging number of up to 6 in quantum rods.

Abstract

Colloidal quantum dots (QDs) are promising optical gain materials that require further threshold reduction to realize their full potential. While QD charging theoretically reduces the threshold to zero, its effectiveness has been limited by strong Auger recombination and unstable charging. Here we theoretically reveal 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. An unprecedented two-order-of-magnitude reduction in nonradiative Auger recombination enables QRs to support a sufficient charging number of up to 6. The QR liquid lasing is then achieved with a near-zero threshold of 0.098 using quasi-continuous pumping of nanosecond pulses, which is the lowest threshold among all reported QD lasers. These achievements demonstrate the potential of the specially engineered QRs as an excellent gain media and pave the way for their prospective applications.