Researchers trap light energy with nanoscale moiré patterns

Physicists at the University of Twente, collaborating with international researchers, have shown for the first time how nanoscale moiré patterns can trap light energy. The study involved stacking two layers of molybdenum disulfide, each only three atoms thick, and rotating the top layer by two degrees.

This rotation created a moiré pattern with a periodicity of nine nanometers, altering how the semiconductor material interacts with light. Using a novel method with an atomically sharp needle and precisely tuned light, researchers mapped the locations where excitons—particle pairs dictating light absorption and emission—are confined.

The team found that different types of excitons settled in different parts of the pattern, remaining trapped in areas approximately two nanometers in size. Crucially, this method operates at room temperature and on real devices, unlike previous techniques often requiring extreme cold.

The research has potential applications in developing ultrasmall light sources, optical sensors, and future materials designed for precise control of light absorption and electricity at the nanoscale.