Graphene’s electrons just broke physics rules, flowing like a perfect, otherworldly quantum liquid. Credit: AI/ScienceDaily.com
Graphene has always been the poster child of futuristic materials, but a new discovery makes it even more puzzling. Scientists at the Indian Institute of Science (IISc) in Bengaluru, working with partners in Japan, found that graphene can violate the Wiedemann–Franz law, a principle that has held strong for metals for more than a century. According to this rule, the way a material conducts electricity and the way it conducts heat should stay linked by a fixed ratio. Graphene, however, didn’t play along. In some experiments, it deviated from the law by more than 200 times, according to ScienceDaily
Here’s what the researchers did. They created ultra-clean graphene samples and cooled them to very low temperatures. At a special point known as the Dirac point, graphene stops behaving like a normal metal and turns into something stranger. Instead of heat and electricity flowing hand-in-hand, they decouple. Electrical conductivity rises, while thermal conductivity drops. The textbook rulebook basically breaks down.
Why does this happen? The team thinks electrons in graphene stop acting like independent particles and instead move collectively like a liquid. Physicists call this state a Dirac fluid. Imagine electrons flowing like water, smooth and almost frictionless, rather than bouncing around like marbles. That fluid-like behavior appears to be the key to why the Wiedemann–Franz law fails so spectacularly.
This isn’t just an academic curiosity. Breaking the link between heat and charge could have big implications for technology. Many advanced devices struggle with heat management. If engineers can harness materials where electricity flows easily but heat does not, it could open the door to better quantum sensors, ultra-efficient electronics, or even more stable superconducting systems.
Of course, there’s a catch. The effect only shows up under very specific conditions: the graphene has to be nearly flawless, the temperature has to be extremely low, and the material has to be tuned just right. Still, the fact that it can happen at all suggests our long-standing understanding of charge and heat transport is incomplete.
Graphene has always been described as “wonder material,” but this result pushes it into almost science-fiction territory. If a single layer of carbon atoms can casually bend the laws of physics, what else might be possible once scientists learn how to fully control it?