Researchers Observe Dirac Fluid in Graphene Violating Wiedemann-Franz Law

Thu, 16 Apr 2026 06:50:00 +0200

Scientists at the Indian Institute of Science (IISc), in collaboration with the National Institute for Materials Science in Japan, have observed electrons in graphene moving like a nearly frictionless fluid, revealing a rare quantum state. By producing ultra-clean graphene samples, the team measured electrical and thermal conductivity and discovered a striking deviation from the Wiedemann-Franz law, which normally links heat and electrical conduction in metals. In their experiments, electrical conductivity increased while thermal conductivity decreased, and vice versa, with deviations exceeding 200 times at low temperatures. This exotic behavior occurs near the 'Dirac point,' where graphene transitions between metallic and insulating states. At this point, electrons behave collectively like a liquid rather than as individual particles, forming what is called a Dirac fluid. The researchers also found that the fluid exhibits extremely low viscosity, making it one of the closest realizati