Hetero-Orbital Two-Component Fractional Quantum Hall States in Bilayer Graphene

Abstract

A two-dimensional electron system exposed to a strong magnetic field produces a plethora of strongly interacting fractional quantum Hall (FQH) states, the complex topological orders of which are revealed through exotic emergent particles, such as composite fermions, fractionally charged Abelian and non-Abelian anyons. Much insight has been gained by the study of multi-component FQH states, where spin and pseudospin indices of the electron contribute additional correlation. Traditional multi-component FQH states develop in situations where the components share the same orbital states and the resulting interactions are pseudospin independent; this homo-orbital nature was also crucial to their theoretical understanding. Here, we study "hetero-orbital" two-component FQH states, in which the orbital index is part of the pseudospin, rendering the multi-component interactions strongly SU(2) anisotropic in the pseudospin space. Such states, obtained in bilayer graphene at the isospin transition between N = 0 and N = 1 electron Landau levels, are markedly different from previous homo-orbital two-component FQH states. In particular, we observe strikingly different behaviors for the parallel-flux and reverse-flux composite fermion states, and an anomalously strong two-component 2/5 state over a wide range of magnetic field before it abruptly disappears at a high field. Our findings, combined with detailed theoretical calculations, reveal the surprising robustness of the hetero-orbital FQH effects, significantly enriching our understanding of FQH physics in this novel regime.

21 pages, 12 figures including appendices

References in corpus (18)

• Even denominator fractional quantum Hall state in bilayer graphene
• Evidence for a Spin Phase Transition at ν=0 in Bilayer Graphene
• Visualizing Broken Symmetry and Topological Defects in a Quantum Hall Ferromagnet
• Thirty Years of Composite Fermions and Beyond
• Wavefunctionology: The Special Structure of Certain Fractional Quantum Hall Wavefunctions
• Crossover between Strongly-coupled and Weakly-coupled Exciton Superfluids
• Valley polarization and susceptibility of composite fermions around nu=3/2
• Valley Isospin Controlled Fractional Quantum Hall States in Bilayer Graphene
• Spinful Composite Fermions in a Negative Effective Field
• Topological Quantum Computing with Read-Rezayi States
• Bilayer WSe${}_2$ as a natural platform for interlayer exciton condensates in the strong coupling limit
• Quantum Phase Transitions and the ν=5/2 Fractional Hall State in Wide Quantum Wells
• Transitions from Abelian composite fermion to non-Abelian parton fractional quantum Hall states in the zeroth Landau level of bilayer graphene
• A non-Abelian fractional quantum Hall state at $3/7$ filled Landau level
• Metallic Phase and Temperature Dependence of the $\nu =0$ Quantum Hall State in Bilayer Graphene
• Competition between fractional quantum Hall liquid and electron solid phases in the Landau levels of multilayer graphene
• Phase diagram of the $\nu =2$ quantum Hall state in bilayer graphene
• Highly-Anisotropic Even-Denominator Fractional Quantum Hall State in an Orbitally-Coupled Half-Filled Landau Level

Cited by in corpus (3)

• Dispersion of collective modes in spinful fractional quantum Hall states on the sphere
• Probing fractional quantum Hall effect by photoluminescence
• Even-denominator fractional quantum Hall states in the zeroth Landau level of ABA trilayer graphene