Light can push around atoms in Janus TMDs, opening the door to faster, cooler, and more sensitive light-based tech. Credit: Shutterstock Researchers at Rice University have found that certain atom-thin semiconductors, known as transition metal dichalcogenides (TMDs), can physically shift their atomic lattice when exposed to light. This newly observed response offers a controllable way to tune the behavior and properties of these ultrathin materials. The phenomenon appears in a subtype of TMDs