Theoretical study of even denominator fractions in graphene: Fermi sea versus paired states of composite fermions

Abstract

The physics of the state at even denominator fractional fillings of Landau levels depends on the Coulomb pseudopotentials, and produces, in different GaAs Landau levels, a composite fermion Fermi sea, a stripe phase, or, possibly, a paired composite fermion state. We consider here even denominator fractions in graphene, which has different pseudopotentials as well as a possible four fold degeneracy of each Landau level. We test various composite fermion Fermi sea wave functions (fully polarized, SU(2) singlet, SU(4) singlet) as well as the paired composite fermion states in the n=0 and $n=1$ Landau levels and predict that (i) the paired states are not favorable, (ii) CF Fermi seas occur in both Landau levels, and (iii) an SU(4) singlet composite fermion Fermi sea is stabilized in the appropriate limit. The results from detailed microscopic calculations are generally consistent with the predictions of the mean field model of composite fermions.

References in corpus (13)

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Cited by in corpus (13)

• Even denominator fractional quantum Hall states at an isospin transition in monolayer graphene
• More Realistic Hamiltonians for the Fractional Quantum Hall Regime in GaAs and Graphene
• Non-Abelian Parton Fractional Quantum Hall Effect in Multilayer Graphene
• Phase Diagram of Fractional Quantum Hall Effect of Composite Fermions in Multi-Component Systems
• Spontaneous polarization of composite fermions in the $n=1$ Landau level of graphene
• Tunable Electron Interactions and Fractional Quantum Hall States in Graphene
• Fermi wave vector for the non-fully spin polarized composite-fermion Fermi sea
• Fractional quantum Hall effect with unconventional pairing in monolayer graphene
• Multi-component fractional quantum Hall states in graphene: SU(4) versus SU(2)
• Graphene in a Strong Magnetic Field: Massless Dirac Particles vs. Skyrmions
• Dynamical Mass Generation of Composite Dirac Fermions and Fractional Quantum Hall Effects near Charge Neutrality in Graphene
• Study of polarization of even-denominator fractional quantum Hall states in SU(4) Graphene
• Repulsive-Interaction-Driven Topological Superconductivity in a Landau Level Coupled to an $s$-Wave Superconductor