A physics professor and his team of students describe a never-before-done technology in an article published this fall that could have implications for screens and other devices that create, change or detect light.

“You come up with these results that are just pleasing to the eye when you do it, and they are scientifically novel — nobody's done it before,” said Matthew White, an associate professor in the Department of Physics, who led the study.

The paper was published in Nature Communications in October.

White and his team of five fabricated a photonic crystal, a structure that can trap and direct light. Light is emitted by injecting electrical current into the crystal. The crystals were created by stacking thin, layered sheets called organic light emitting diodes (better known as OLEDs,) which are used within handheld and TV displays.

Using reflecting semi-transparent mirrors on the sides of an OLED sheet, the team was able to create a structure called a microcavity. It acts like a guitar string: where varying the tension produces different sounds, varying the distances of the mirrors tunes the color of light emitted.

“We hadn't seen microcavity OLEDs stacked into a photonic crystal before,” White said, “so this project has been something I've had in mind for a long time.”

White’s work focuses on optoelectronics — the study of light-emitting and light-detecting devices —and materials physics. He teaches courses in physics for undergraduates.

The appeal in cost efficiency and functionality in electronic consumer devices has increased throughout the years. White and his team believe there are implications in their research for more technologically advanced structures leading to photonic devices — devices that create, manipulate or detect light — with a higher degree of functional control.

White credits graduate student David Allemeier for getting the ball rolling on the project.

“It was when (Allemeier) and I sat down,” said White, “and we devised this photonic band theory that explains everything we're seeing.”

Among the authors of the journal article are then-undergraduate Benjamin Isenhart, whom White described as one of the first students to start working on the project as part of his honor’s thesis.

White described it as a “high impact” achievement going forward in all the students’ careers.

Co-authors Ekraj Dahal, a UVM graduate student,Yuki Tsuda and Tsukasa Yoshida, a graduate student and professor at Yamagata University in Japan, were credited by White for their efforts.

Tsuda was part of the team as a visiting scholar at UVM in spring of 2020, a chaotic time for research. White said Tsuda continuously worked on the project from Japan after having to leave Burlington due to the Covid-19 pandemic. The stateside team would mail samples to Japan for Tsuda to cut using a special instrument called a focused ion beam, then mail back.

“I'm very proud of their work,” White said. “And I'm really proud of them.”

White is interested in branching out their work with further research. “It's kind of an iterative process that I hope never ends,” he said.

One possibility he described would be refining the photonic crystal by using optically and electronically better materials to get more precise results.

“With any of these projects,” White said, “when you make forward progress, you open up more questions that need answering — and more opportunities to do better.”

McKenzie Kelley is a junior biology major with an interest in telling stories about scientists.