Even-denominator Fractional Quantum Hall Effect at a Landau Level Crossing

Abstract

The fractional quantum Hall effect (FQHE), observed in two-dimensional (2D) charged particles at high magnetic fields, is one of the most fascinating, macroscopic manifestations of a many-body state stabilized by the strong Coulomb interaction. It occurs when the filling factor ($\nu$) of the quantized Landau levels (LLs) is a fraction which, with very few exceptions, has an odd denominator. In 2D systems with additional degrees of freedom it is possible to cause a crossing of the LLs at the Fermi level. At and near these crossings, the FQHE states are often weakened or destroyed. Here we report the observation of an unusual crossing of the two \emph{lowest-energy} LLs in high-mobility GaAs 2D $hole$ systems which brings to life a new \emph{even-denominator} FQHE at $\nu =1/2$.

References in corpus (11)

• Non-Abelian Anyons and Topological Quantum Computation
• Valley susceptibility of an interacting two-dimensional electron system
• Observation of even denominator fractional quantum Hall effect in suspended bilayer graphene
• Observation of Quantum Hall Valley Skyrmions
• Observation of a Fractional Quantum Hall State at $\nu =1/4$ in a Wide GaAs Quantum Well
• Quantum Hall Phase Diagram of Half-filled Bilayers in the Lowest and the Second Orbital Landau Levels: Abelian versus Non-Abelian Incompressible Fractional Quantum Hall States
• Phase Diagrams for the $\nu$ = 1/2 Fractional Quantum Hall Effect in Electron Systems Confined to Symmetric, Wide GaAs Quantum Wells
• Interaction-tuned compressible-to-incompressible phase transitions in the quantum Hall systems
• Fractional quantum Hall effects in bilayers in the presence of inter-layer tunneling and charge imbalance
• Fractional quantum Hall state at ν=1/4 in a wide quantum well
• Fractional Quantum Hall Effect at $\nu =1/2$ in Hole Systems Confined to GaAs Quantum Wells

Cited by in corpus (28)

• Even denominator fractional quantum Hall states at an isospin transition in monolayer graphene
• Recent Experimental Progress of Fractional Quantum Hall Effect: 5/2 Filling State and Graphene
• A cascade of phase transitions in an orbitally mixed half-filled Landau level
• Even-Denominator Fractional Quantum Hall State at Filling Factor ν = 3/4
• Geometric Resonance of Composite Fermions near Bilayer Quantum Hall States
• Composite Fermions with a Warped Fermi Contour
• $\nu =1/2$ Fractional Quantum Hall Effect in Tilted Magnetic Fields
• Composite fermion pairing induced by Landau level mixing
• Record-quality GaAs two-dimensional hole systems
• Fractional Quantum Hall State at Filling Factor $\nu =1/4$ in Ultra-High-Quality GaAs 2D Hole Systems
• Robust Quantum Hall Ferromagnetism near a Gate-Tuned ν = 1 Landau Level Crossing
• Topological exciton Fermi surfaces in two-component fractional quantized Hall insulators
• Observation of An Anisotropic Wigner Crystal
• Spin Reversal of a Quantum Hall Ferromagnet at a Landau Level Crossing
• SU(3) and SU(4) singlet quantum Hall states at $\nu =2/3$
• Microwave spectroscopic observation of a Wigner solid within the 1/2 fractional quantum Hall effect
• Tilt-Induced Phase Transitions in Even-Denominator Fractional Quantum Hall States at the ZnO Interface
• Unusual Landau Level Pinning and Correlated $\nu =1$ Quantum Hall Effect in Hole Systems Confined to Wide GaAs Quantum Wells
• Highly-Anisotropic Even-Denominator Fractional Quantum Hall State in an Orbitally-Coupled Half-Filled Landau Level
• Valley-tunable, even-denominator fractional quantum Hall state in the lowest Landau level of an anisotropic system
• Morphing of 2D Hole Systems at $\nu =3/2$ in Parallel Magnetic Fields: Compressible, Stripe, and Fractional Quantum Hall Phases
• Ultraclean two-dimensional hole systems with mobilities exceeding 10${}^7$ cm${}^2$/Vs
• Incompressible Even Denominator Fractional Quantum Hall States in the Zeroth Landau Level of Monolayer Graphene
• Competing Many-Body Phases at Small Fillings in Ultrahigh-Quality GaAs 2D Hole Systems: Role of Landau Level Mixing
• Hetero-Orbital Two-Component Fractional Quantum Hall States in Bilayer Graphene
• Fractional quantum Hall state at $\nu =1/2$ with energy gap up to 6 K, and possible transition from one- to two-component state
• Interaction-driven quantum phase transitions between topological and crystalline orders of electrons
• Even-denominator fractional quantum Hall states with spontaneously broken rotational symmetry