Nanowerk July 19, 2021 The quantum Hall effect is the seminal example of topological protection as charge carriers are transmitted through one-dimensional edge channels where backscattering is prohibited. In conventional Hall bar geometries, topological protection of graphene edge channels is found less robust than in high mobility semi-conductors. An international team of researchers (Belgium, Germany, Japan) exploring graphene quantum Hall regime at the local scale revealed that the detrimental influence of antidots along the graphene edges, mediating backscattering towards upstream edge channels triggering topological breakdown. The finding is a major step forward in the understanding of the quantum Hall effect […]
Category Archives: Graphene
Physicists find misaligned carbon sheets yield unparalleled properties
Science Daily July 31, 2020 In an earlier study an international team of researchers (Yale University, UT Dallas, Japan) showed that when offset by 0.93 degrees, twisted bilayer graphene exhibits both superconducting and insulating states, thereby widening the magic angle significantly. In the current research they set out to determine how mid-infrared light might affect the conductance of electrons in twisted bilayer graphene. Their work involved calculating the light absorption based on the moiré pattern’s band structure. They showed that the theoretical results not only matched well with the experimental findings, but also pointed to a mechanism that is fundamentally […]
Nanotube ‘rebar’ makes graphene twice as tough
Science Daily August 4, 2018 In 2014 Rice University researchers developed Rebar graphene that consists of CNTs embedded in graphene. An international team of researchers (USA – Rice University, University of Maine, Brown University, China) implemented a “dry” transfer technique to test the freely suspended rebar graphene under uniaxial tension mode. Combined experiments and molecular dynamics simulations confirmed that the embedded CNTs divert and bridge the propagating crack and provide a toughening mechanism for the material. This is a promising extrinsic toughening strategy for 2D materials and provides mechanistic insights into the fracture process of graphene hybrid material. The experiments […]