Graphene, a revolutionary material with a single layer of carbon atoms, continues to fascinate scientists with its unique electronic properties. A recent study delves into the behavior of monolayer graphene when subjected to a Uniform Magnetic Field, unveiling intriguing quantum phenomena and potential applications. This research explores both non-interacting and interacting electron scenarios within graphene under these conditions.
In the absence of interactions, the study highlights the emergence of 2q Dirac points within the Brillouin zone for specific magnetic flux configurations. These points, protected by chiral symmetry and the honeycomb lattice structure, are crucial for graphene’s unique electronic behavior. Furthermore, the research investigates how these Dirac points respond to symmetry-breaking perturbations, such as staggered potentials and next-nearest-neighbor hopping, revealing a topological phase transition driven by the competition between these factors.
Moving to the more complex interacting case, the study explores the phases of graphene in a strong uniform magnetic field, considering on-site Hubbard and nearest-neighbor Heisenberg interactions. The findings reveal a rich phase diagram with co-existing phases predicted in continuum limits, such as ferromagnetic, antiferromagnetic, charge density wave, and Kekulé distorted phases. Intriguingly, the research also uncovers phases not previously anticipated in continuum models, expanding our understanding of graphene’s behavior under strong magnetic influence.
This comprehensive study enhances our fundamental knowledge of graphene in a uniform magnetic field, providing valuable insights into its quantum properties and paving the way for future explorations in condensed matter physics and materials science. Further details can be found in the full dissertation by Ankur Das from the University of Kentucky (https://doi.org/10.13023/etd.2020.228).
