- August 25, 2026
- By Daniela Benites
A University of Maryland researcher studying the optical properties of a two-dimensional material noticed unusual behavior in his sample—turns out, he was looking at vibrations of electron crystals, revealing new insights into these quantum states of matter.
The study was a first in observing the internal dynamics of “Wigner crystals,” semiconductor materials that only realize under limited conditions. The paper was published by You Zhou, an associate professor in the Department of Materials Science and Engineering, for the journal Nature Physics.
"Most work on Wigner crystals has asked a yes-or-no question: is the crystal there? We found ourselves able to answer a different one: what is it actually doing?" said Zhou. "That was not by design. It was a discovery by accident."
Wigner crystals, unlike conventional crystals made of atoms, are formed only by electrons. They are named after Eugene Wigner, the Nobel Laureate physicist who predicted them in 1934. Since then, only a handful of experiments have demonstrated their existence due to their fragile nature. Electron crystallization only occurs at very low temperatures, and with very low electron density, presenting many experimental challenges to realize them. They are so delicate that conventional experimental techniques can’t be used to study the properties of such crystals, for example, how they vibrate.
Zhou’s experiments established a way to detect the phenomenon, using an optical system that measured the crystals’ vibration qualities, known as their “phonon” properties. These are key to understanding how the crystals behave, which informs future applications. Currently, these materials are of interest to the electronics and optical device research communities due to their ability to switch between different states.
Now, he hopes to solve new questions about the rare semiconductor materials, with his team working on ways to use light to switch a material from one state of matter to another at very high speeds.