Researchers discover self-forming p-n junction

Scientists studying a promising quantum material called MnBi₆Te₁₀ have stumbled upon a surprise: within its crystal structure, the material naturally forms one of the world’s thinnest semiconductor junctions. The p-n junction is 3.3 nm thick.

They reported their work 'Spectroscopic evidence of intra-unit-cell charge redistribution in a charge-neutral magnetic topological insulator,' in the journal Nanoscale, in April 2025

“This was a big surprise,” said Shuolong Yang, an assistant professor at the University of Chicago Pritzker School of Molecular Engineering (UChicago PME). “We weren’t trying to make this junction, but the material made one on its own, and it’s one of the thinnest we’ve ever seen.”