In his second year of graduate school, Dane deQuilettes thought something was wrong with his microscope. He had just returned to the University of Washington from the University of Oxford, where he had learned to make perovskites—polycrystalline solar materials that can be printed like ink—and he was eager to see what the film would reveal. But the image looked wrong. He was convinced he had botched the calibration and spent days troubleshooting in secret.
The microscope was fine. He discovered that the problem was the material.
On supporting science journalism
If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.
In 2015 perovskites were becoming more efficient than other solar materials people were researching, raising hopes that they could be turned into cheap, high-performance solar cells. But deQuilettes accidentally discovered that one of the field’s early assumptions was wrong. Researchers had thought perovskite films were uniform. He revealed that they were instead a patchwork of crystals, some performing beautifully while others leaked energy through defects. The finding redirected solar researchers toward neutralizing those defects—and established deQuilettes as one of the scientists pushing a hyped material toward a more exacting science.

Jeffery DelViscio
DeQuilettes grew up in central Washington State. He was known as an athlete, but he’d often sneak away to compete in Science Olympiad, wary of being pegged as the nerdy kid. When he told his mother he wanted to study chemistry, she worried it would not pay enough to build a life on; he came back with a salary survey.
DeQuilettes joined Princeton University earlier this year, and now he is building the Quantum and Emerging Semiconductor Technologies Lab. He’s still working on solar materials, but he has widened his scope into quantum sensing, using diamond crystals with tiny, engineered defects that act as exquisitely sensitive probes of their surroundings.
“Every field reaches the edge of the unknown,” he says. “It’s a mystery, and you get to learn really fast. That’s what excites me.”
This article is part of “The Young American Scientists,” an editorially independent project that was produced with financial support from Regeneron.

