Just over a year after researchers at MIT stunned the physics world with the discovery of the "magic angle" for stacked sheets of graphene, researchers at Caltech have directly observed and studied this material using a scanning tunneling microscope that can image electronic properties at atomic-length scales.
Understanding the "magic angle"—a specific orientation between the stacked graphene that yields special electric properties—could pave the way to realizing the dream of room-temperature superconductors, which could transmit enormous electric currents while producing zero heat.
But first: what is the magic angle? Say you take two sheets of graphene—single-atom thick lattices of carbon atoms—and lay one atop the other to create a bilayer material, then twist one of the sheets of graphene to shift their orientation to one another. As the orientation shifts, the electronic properties of the bilayer material will change with it. In early 2018, researchers at MIT discovered that, at a certain orientation (about 1.1 degrees of relative twist), the bilayer material, surprisingly, becomes superconducting and moreover, the superconducting properties can be controlled with the electric fields. Their discovery launched a new field of research into magic angle-oriented graphene, known as "twistronics."To read more, click here.