Inside every smartphone and computer chip, invisible imperfections float in the solid materials that make these devices work. These tiny defects — smaller than a human hair sliced a thousand times — can absorb and release energy in ways that either help or hurt how well the device functions. Now, scientists have built a free computer tool that can predict exactly how that energy moves around, potentially opening the door to much more powerful devices someday.
The tool is called PyRET, short for Python package for Resonance Energy Transfer. It was created by researchers at Argonne National Laboratory in Illinois and the University of Chicago. Swarnabha Chattaraj, a postdoctoral researcher at Argonne who led the software's development, said the tool solves a long-standing puzzle in materials science: how to connect what happens to electrons at the tiniest scales — less than a billionth of a meter — with how light behaves across much larger distances inside a device.
"For many advanced devices, it is important to know how one defect interacts with another," Chattaraj said. "PyRET gives us a way to calculate the energy transfer rates between defects from first principles — starting from the atomic structure of the material and the known laws of physics — rather than relying on fitted experimental data or rough approximations."
When one defect in a material gets energized, it can release that energy as light, which then gets absorbed by a nearby defect. PyRET models exactly how this handoff happens by combining detailed information about each defect's electronic structure with a quantum-level description of how the defects absorb or emit light.
Using PyRET, Chattaraj and his collaborators made another striking discovery: they found that a photonic cavity — a tiny structure that traps and shapes light at specific colors — can dramatically change how fast energy moves between defects. By adjusting the cavity, they were able to speed up or slow down energy transfer by nearly one hundred times.
That kind of control could be crucial for building new kinds of optical memory devices that store far more data in the same amount of space than today's technologies allow. It might also help scientists understand and reduce unwanted energy leaks in quantum computing systems.
Unlike some scientific tools that stay locked away in university labs, PyRET is free and open to anyone. Scientists anywhere can download it, test it and improve it, which the researchers hope will accelerate progress in both basic research and real device design.
In the long term, PyRET could help engineers build materials that store and control information more efficiently — work that might one day show up in the devices people use every day.