A Korean research team has discovered a new physical phenomenon that enables precise control of exciton movement and dramatically amplifies exciton diffusion — a breakthrough that could help address the growing power crisis driven by artificial intelligence.
A research team led by Professor Park Kyoung-duck at POSTECH (Pohang University of Science and Technology) announced on June 3 that it became the first in the world to discover a new physical phenomenon that precisely controls exciton movement in two-dimensional semiconductors at the nanometer (one-billionth of a meter) scale and amplifies diffusion by up to 8,300% compared to conventional methods.
Current semiconductors use the flow of electrons to transmit information. However, electron movement inevitably generates heat, leading to energy loss and performance degradation. AI data centers now consume power equivalent to an entire city, underscoring the severity of the energy problem.
Excitons have emerged as a next-generation ultra-low-power information carrier that could solve this challenge. An exciton is a particle inside a semiconductor that combines the properties of light and electrons. Because it is electrically neutral, it generates virtually no heat during movement. Until now, however, precisely controlling excitons as desired has been extremely difficult, limiting practical device applications.
To overcome this barrier, Professor Park's team developed a new nano-resonance spectroscopy technique capable of freely manipulating light and electricity at the nanometer scale. The technique concentrates light and electric fields into ultra-fine spaces comparable to the minimum line width of cutting-edge semiconductor fabrication processes. This enabled the team to precisely control and simultaneously observe the "energy landscape" inside semiconductors at the nanoscale.
In applying the new technique, the team also demonstrated exciton diffusion amplification of up to 8,300% compared to conventional methods.
Dr. Lee Hyung-woo, a member of the research team, concentrated excitons into a specific narrow region and discovered that the gathered excitons repel each other, spreading outward even faster and more powerfully. The team found that this phenomenon is determined not simply by the number of excitons but by the "density gradient" — how steeply the excitons are concentrated.
This amplification effect can also be controlled in real time using voltage alone. "Simply by adjusting voltage, we can freely change the direction and intensity of exciton movement," the team said. "This has strong potential to lead to technology that transmits information quickly and efficiently inside semiconductor chips."
