Researchers at the University of Oklahoma have made significant progress addressing photoluminescence blinking and photodarkening in lead halide perovskite Quantum Dots (QDs), which have historically limited their use in quantum applications. Led by Assistant Professor Yitong Dong, the team explored solid-state ligand tail engineering, demonstrating that attractive intermolecular interactions between low-steric ligand tails can create a nearly epitaxial ligand layer that dramatically reduces surface energy.
Their approach uses stacked phenethylammonium ligands to cover CsPbBr3 quantum dots, resulting in remarkable performance improvements: nearly non-blinking single photon emission with high purity (~98%) and extraordinary photostability lasting over 12 hours under continuous operation and saturated excitations. This crystallized molecular layer effectively neutralizes surface defects and stabilizes the atomic structure of the QDs.
Unlike traditional quantum emitters that require extremely low cryogenic temperatures (-452°F), these perovskite QDs function efficiently at room temperature, making them significantly more practical and cost-effective for real-world applications. Previous QDs typically failed after only 10-20 minutes, while these stabilized versions maintain continuous photon emission for more than 12 hours without decay or significant blinking.
This achievement is particularly noteworthy given the minuscule size of quantum dots—if a single QD were enlarged to the size of a baseball, a baseball would be as large as the Moon. The ability to stabilize particles at this scale represents a remarkable feat of nanoscale engineering and materials science, with applications extending to computer monitors, LEDs, solar cells, biomedical devices, and secure communication technologies beyond quantum computing.
This breakthrough has profound implications for quantum computing and communication, potentially establishing perovskite QDs as the preferred photonic chip light source for future quantum devices. The research also creates opportunities for further exploration of fundamental optical properties and physics of these materials, extending beyond this specific material or molecular structure to influence future quantum emitter designs using organic and inorganic molecular crystals.
Reference: “Towards non-blinking and photostable perovskite quantum dots” by Chenjia Mi, Gavin C. Gee, Chance W. Lander, Donghoon Shin, Matthew L. Atteberry, Novruz G. Akhmedov, Lamia Hidayatova, Jesse D. DiCenso, Wai Tak Yip, Bin Chen, Yihan Shao and Yitong Dong, 2 January 2025, Nature Communications. DOI: 10.1038/s41467-024-55619-7
