title: Flux States and Topological Phases from Spontaneous Time-Reversal Symmetry Breaking in CrSi(Ge)Te_{3}-Based Systems.
abstract: We study adatom-covered single layers of CrSiTe_{3} and CrGeTe_{3} using first-principles calculations based on hybrid functionals. We find that the insulating ground state of a monolayer of La (Lu) deposited on single-layer CrSiTe_{3} (CrGeTe_{3}) carries spontaneously generated current loops around the Cr sites. These "flux states" induce antiferromagnetically ordered orbital moments on the Cr sites and are also associated with nontrivial topological properties. The calculated Chern numbers for these systems are predicted to be ±1 even in the absence of spin-orbit coupling, with sizable gaps on the order of 100 meV. The flux states and the associated topological phases result from spontaneous time-reversal symmetry breaking due to the presence of nonlocal Coulomb interactions.
authors.affiliation: Kavli Institute for Theoretical Physics, University of California, Santa Barbara, California 93106, USA.|Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA.
authors.forename: Jianpeng
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA.
authors.forename: Se Young
authors.initials: SY
authors.lastname: Park
authors.affiliation: Material Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
authors.forename: Kevin F
authors.initials: KF
authors.lastname: Garrity
authors.affiliation: Department of Physics and Astronomy, Rutgers University, Piscataway, New Jersey 08854-8019, USA.
authors.forename: David
authors.initials: D
authors.lastname: Vanderbilt