News from the NNI Community - Research Advances Funded by Agencies Participating in the NNI

In 2018, scientists discovered that two layers of graphene that are twisted one with respect to the other by a very small, well-defined angle show a variety of interesting quantum phases, including superconductivity, magnetism, and insulating behaviors. Now, a team of researchers from MIT and the Weizmann Institute of Science in Israel have discovered that these quantum phases come from a previously unknown high-energy “parent state,” with an unusual breaking of symmetry.

Scientists at Rice University have identified a small set of two-dimensional compounds that, when placed together, allow excitons to form spontaneously. Excitons are quasiparticles that exist when electrons and holes briefly bind; they generally happen when energy from light or electricity boosts electrons and holes into a higher state. But in a few of the combinations predicted by the scientists, excitons were observed stabilizing at the materials' ground state. The discovery shows promise for electronic, spintronic, and quantum computing applications.

Scientists at Rice University have identified a small set of two-dimensional compounds that, when placed together, allow excitons to form spontaneously. Excitons are quasiparticles that exist when electrons and holes briefly bind; they generally happen when energy from light or electricity boosts electrons and holes into a higher state. But in a few of the combinations predicted by the scientists, excitons were observed stabilizing at the materials' ground state. The discovery shows promise for electronic, spintronic, and quantum computing applications.

Among the unique qualities of graphene is that layers of it can be stacked on top of each other, like Lego pieces, to create artificial electronic materials. But efficient methods for building these structures – and, more generally, atomically thin graphene-like materials that are placed on top of each other – are still lacking. Now, a team of researchers from New York University and the National Institute for Materials Science in Japan has found a versatile method for the construction of these structures.

Among the unique qualities of graphene is that layers of it can be stacked on top of each other, like Lego pieces, to create artificial electronic materials. But efficient methods for building these structures – and, more generally, atomically thin graphene-like materials that are placed on top of each other – are still lacking. Now, a team of researchers from New York University and the National Institute for Materials Science in Japan has found a versatile method for the construction of these structures.

Among the unique qualities of graphene is that layers of it can be stacked on top of each other, like Lego pieces, to create artificial electronic materials. But efficient methods for building these structures – and, more generally, atomically thin graphene-like materials that are placed on top of each other – are still lacking. Now, a team of researchers from New York University and the National Institute for Materials Science in Japan has found a versatile method for the construction of these structures.

Among the unique qualities of graphene is that layers of it can be stacked on top of each other, like Lego pieces, to create artificial electronic materials. But efficient methods for building these structures – and, more generally, atomically thin graphene-like materials that are placed on top of each other – are still lacking. Now, a team of researchers from New York University and the National Institute for Materials Science in Japan has found a versatile method for the construction of these structures.

A research team at The City University of New York, in collaboration with The University of Texas at Austin, National University of Singapore, and Monash University in Australia, has used ''twistronics'' concepts (the science of layering and twisting two-dimensional materials to control their electrical properties) to manipulate the flow of light. The findings hold the promise for advances in a variety of light-driven technologies, including nano-imaging devices; high-speed, low-energy optical computers; and biosensors.

A research team at The City University of New York, in collaboration with The University of Texas at Austin, National University of Singapore, and Monash University in Australia, has used ''twistronics'' concepts (the science of layering and twisting two-dimensional materials to control their electrical properties) to manipulate the flow of light. The findings hold the promise for advances in a variety of light-driven technologies, including nano-imaging devices; high-speed, low-energy optical computers; and biosensors.

Place a single sheet of carbon atop another at a slight angle, and remarkable properties emerge, including the resistance-free flow of current known as superconductivity. Now, a team of researchers at Princeton has looked for the origins of this unusual behavior in a material known as magic-angle twisted bilayer graphene and detected signatures of a cascade of energy transitions that could help explain how superconductivity arises in this material.