Doped Perovskite Quantum Dots as a Single-Photon Sources with Enhanced Stability

We have unveiled a simple yet powerful way to greatly enhance the stability of perovskite quantum dots – tiny light-emitting nanocrystals poised to play an important role in next-generation quantum communication and computing. The advance could accelerate the transition from expensive, epitaxially-grown materials to affordable, solution-processed components suitable for real-world quantum technologies.

The team discovered that introducing just a trace amount of nickel during a rapid, room-temperature synthesis produces CsPbBr₃ quantum dots that remain remarkably stable under everyday environmental conditions and stressors. This simple chemical adjustment allows the nanocrystal quantum dots to maintain bright, clean optical emission without degrading or blinking, even at normal humidity levels.

Notably, the nickel-doped quantum dots act as high-quality single-photon sources, emitting one photon at a time with exceptionally high purity. This level of performance is rarely achieved under ambient conditions, and it marks a key step toward building robust quantum-optical systems.

By combining stability, scalability, and excellent quantum-emission quality, the work demonstrates a practical and cost-effective route to quantum light sources. The findings open new possibilities for integrating perovskite nanomaterials into quantum communication hardware, photonic chips, and compact sensing technologies – bringing the vision of accessible quantum devices one step closer to reality.

Collaboration:

• Centro de Física de Materiales (CFM-MPC)
• Donostia International Physics Center (DIPC)
• Departamento de Química Física, Universidad del País Vasco, UPV/EHU