Quantum Hall ferromagnets and transport properties of buckled Dirac materials
arXiv:1506.07896 · doi:10.1103/PhysRevB.92.155123
Abstract
We study the ground states and low-energy excitations of a generic Dirac material with spin-orbit coupling and a buckling structure in the presence of a perpendicular magnetic field. The ground states can be classified into three types under different conditions: SU(2), easy-plane, and Ising quantum Hall ferromagnets. For the SU(2) and the easy-plane quantum Hall ferromagnets there are goldstone modes in the collective excitations, while all the modes are gapped in an Ising-type ground state. We compare the Ising quantum Hall ferromagnet with that of bilayer graphene and present the domain wall solution at finite temperatures. We then specify the phase transitions and transport gaps in silicene in Landau levels 0 and 1. The phase diagram strongly depends on the magnetic field and the dielectric constant. We note that there exists triple points in the phase diagrams in Landau level N = 1 that could be observed in experiments.
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References in corpus (12)
- Valley polarized quantum Hall effect and topological insulator phase transitions in silicene
- The Fractional Quantum Hall States of Dirac Electrons in Graphene
- Quantum Hall Effects in Silicene
- Controllable, driven phase transitions in the Fractional quantum Hall states in bilayer graphene
- Long range Coulomb interaction in bilayer graphene
- SO(5) symmetry in the quantum Hall effect in graphene
- Collective Edge Modes near the onset of a graphene quantum spin Hall state
- Collective modes of CP(3) Skyrmion crystals in quantum Hall ferromagnets
- Spontaneous Layer Polarization and Conducting Domain Walls in the Quantum Hall Regime of Bilayer Graphene
- Tunability of the Fractional Quantum Hall States in Buckled Dirac Materials
- Transport gap and hysteretic behavior of the Ising quantum Hall ferromagnets in Landau levels of bilayer graphene
- Ising quantum Hall ferromagnetism in Landau levels of bilayer graphene