A material best known for its promise in affordable solar cells has just revealed another astonishing talent — producing light at incredible speeds.
Scientists have discovered that halide perovskites, already famous for their use in next-generation solar technology, can emit light faster than almost any semiconductor on the market, marking a major step toward ultrafast quantum devices.
The study, published in Nature Nanotechnology, shows that specially prepared films of formamidinium lead iodide can generate quantum light pulses lasting just two trillionths of a second (two picoseconds) when cooled to low temperatures.
These lightning-fast events—called quantum transients—suggest that perovskites could play a key role in creating faster light sources and quantum communication systems.
What makes this discovery especially exciting is that it doesn’t rely on rare or expensive materials.
The films were made using scalable solution and vapor processing methods, similar to those already used in solar cell manufacturing.
This means the results could translate into practical, low-cost technologies rather than being limited to laboratory experiments.
“Perovskites continue to surprise us,” said Professor Sam Stranks, who led the research.
“Their nanoscale structure gives rise to unique quantum properties that we’re only beginning to understand—and these could be harnessed for next-generation photonic technologies.”
Using a combination of ultrafast spectroscopy, optical microscopy, and electron microscopy, Stranks’ team traced the rapid light emission to quantum tunneling occurring within tiny, ordered regions of the material known as nanodomain superlattices.
These alternating structural zones create the perfect conditions for electrons and holes—the charged particles that carry current—to recombine and emit light almost instantly.
Dr. Dengyang Guo, one of the study’s lead authors, said the findings expand the potential of perovskites far beyond solar energy.
“Seeing these ultrafast effects in scalable films is thrilling,” he said. “It shows perovskites have even more to offer than we thought.”
Ph.D. student Tom Selby, who co-led the experiments, added, “Being able to trace the light emission back to the material’s structure has been an eye-opener—it’s exciting to think where this could lead.”
While the results are groundbreaking, the team notes that the experiments were performed at low temperatures. Future studies will need to test whether these quantum effects remain stable at room temperature and meet the rigorous standards required for quantum optics applications, such as single-photon emission.
Still, the discovery highlights once again how halide perovskites—a class of materials originally studied for solar power—may also hold the key to affordable, ultrafast light sources and quantum communication technologies of the future.
