Researchers from The Ohio State University, the University of Texas at Dallas, and the National Institute for Materials Science in Tsukuba, Japan, have shown that quantum geometry plays a key role in allowing graphene, when twisted to a precise angle – called the magic angle – to become a superconductor, moving electricity with no loss of energy. In a conventional metal, high-speed electrons are responsible for conductivity. But twisted bilayer graphene has a type of electronic structure in which the electrons move very slowly – in fact, at a speed that approaches zero if the angle is exactly at the magic one. "We can't use the speed of electrons to explain how the twisted bilayer graphene is working," said Marc Bockrath, one of the scientists involved in this study. "Instead, we had to use quantum geometry."
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