Date Available
5-13-2025
Year of Publication
2025
Document Type
Doctoral Dissertation
Degree Name
Doctor of Philosophy (PhD)
College
Arts and Sciences
Department/School/Program
Physics and Astronomy
Faculty
Ganpathy Murthy
Faculty
Anatoly Dymarsky
Abstract
In the presence of a perpendicular magnetic field, monolayer graphene at and near charge neutrality forms a quantum Hall ferromagnet—a correlated electronic state where the interplay of interactions, spin, and valley degrees of freedom leads to spontaneous symmetry breaking. While the dominant Coulomb interaction has $SU(4)$ symmetry, the ground state is ultimately determined by subdominant terms: residual lattice-scale anisotropic interactions, Zeeman, and sublattice couplings. Relaxing the ultra-short-range limit of anisotropic interactions unveils diverse symmetry-breaking phases in both integer and fractional quantum Hall regimes. Haldane pseudopotentials, which quantify interactions between particle pairs with fixed relative angular momentum, provide a readily parameterizable framework for anisotropic interactions, enabling the construction of a variational energy functional via the combined use of exact diagonalization and Hartree-Fock approximation. In this thesis, we systematically explore emergent symmetry-breaking phases at both integer and fractional fillings in monolayer graphene Landau levels.
Digital Object Identifier (DOI)
https://doi.org/10.13023/etd.2025.202
Funding Information
This study was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC-0024346.
Recommended Citation
An, Jincheng, "Quantum Hall Phases in Monolayer Graphene" (2025). Theses and Dissertations--Physics and Astronomy. 135.
https://uknowledge.uky.edu/physastron_etds/135
