Discovery of bistable nanocrystals promises faster, more energy-efficient optical computing

With the discovery of light-emitting nanocrystals that can quickly switch from light to dark, scientists including chemistry researchers at Oregon State University have taken an important step toward faster and more energy-efficient artificial intelligence and data processing in general. I took a step.

“The extraordinary switching and storage capabilities of these nanocrystals could one day lead to optical computing, a way to rapidly process and store information using particles of light that travel faster than anything in the universe,” said Artyom Skripka, an assistant professor at OSU. It may become indispensable.” Faculty of Science.

The study published in Nature Photonics by Skripka and colleagues at Lawrence Berkeley National Laboratory, Columbia University, and Universidad Autónoma de Madrid involves a type of material known as avalanche nanoparticles.

Nanomaterials are small substances ranging from 1 billionth to 100 billionth of a meter, and the nanoparticles that cause avalanches are characterized by extremely nonlinear emission properties. Nanomaterials can produce large increases in intensity with only small increases in the amount of light they emit. The intensity of the laser excites them.

The researchers studied nanocrystals made of potassium, chlorine, and lead and doped with neodymium. KPb2Cl5 nanocrystals themselves do not interact with light. However, as a host, neodymium guest ions can process optical signals more efficiently, making them useful for optoelectronics, laser technology, and other optical applications.

“Normally, luminescent materials emit light when excited by a laser, but otherwise remain dark,” Skripka says. “In contrast, we were surprised to learn that our nanocrystals live in parallel. Under certain conditions, nanocrystals exhibit peculiar behavior. Under exactly the same laser excitation wavelength and power So it gets brighter or darker.”

This behavior is called intrinsic optical bistability. The inherent optical bistability of nanocrystals is an advance toward photonic integrated circuits, which have the potential to exhibit superior performance with efficiency exceeding current electronic and optoelectronic systems.

“If the crystal is dark to begin with, it will require a higher laser power to turn it on and see it emit light, but once it does, it will emit light at a lower laser power than what was needed to turn it on in the first place. We will be able to observe it,” Skripka said. . “It’s like riding a bike. You have to push hard on the pedals to get the bike moving, but once it starts moving, it doesn’t take much force to keep going. You can turn it on and off very suddenly as if by pressing the button. ”

Nanocrystals’ low-power switching capabilities are in line with global efforts to reduce the amount of energy consumed by the growing presence of artificial intelligence, data centers and electronic devices, he added. AI applications require significant computational power and are often constrained by limitations associated with existing hardware, a situation that this new research could potentially address.

“Integrating photonic materials with their inherent optical bistability means faster and more efficient data processors, with the potential to power machine learning algorithms and data analysis,” Skripka said. “It could also mean more efficient light-based devices, of the type used in fields such as telecommunications, medical imaging, and environmental sensing.”

Additionally, he said this work complements existing efforts to develop powerful general-purpose optical computers based on the behavior of light and matter at the nanoscale, and supports fundamental research in driving innovation and economic growth. He said that he emphasized the importance of

“While our discovery is an exciting development, further research is needed to address challenges such as scalability and integration with existing technologies before our discovery can be put into practical use,” Skripka said. said.