High-Resolution Tunneling Spectroscopy of Fractional Quantum Hall States

Abstract

Strong interaction between electrons in two-dimensional systems in the presence of a high magnetic field gives rise to fractional quantum Hall states that host quasiparticles with fractional charge and fractional exchange statistics. Here, we demonstrate high-resolution scanning tunneling microscopy and spectroscopy of fractional quantum Hall states in ultra clean Bernal-stacked bilayer graphene devices. Spectroscopy measurements show sharp excitations that have been predicted to emerge when electrons fractionalize into bound states of quasiparticles. We find energy gaps for candidate non-abelian fractional states that are larger by a factor of five than other related systems - for example semiconductor heterostructures - and this suggests bilayer graphene is an ideal platform for the manipulation of these quasiparticles and for the creation of a topological quantum bit. We also find previously unobserved fractional states in our very clean graphene samples.

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References in corpus (14)

• Non-Abelian Anyons and Topological Quantum Computation
• Fractional statistics in anyon collisions
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• Even denominator fractional quantum Hall state in bilayer graphene
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• High Resolution Spectroscopy of Two-Dimensional Electron Systems
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• Topological blockade and measurement of topological charge
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Cited by in corpus (10)

• Microscopic Mechanism of Anyon Superconductivity Emerging from Fractional Chern Insulators
• Critical Majorana fermion at a topological quantum Hall bilayer transition
• Fractional quantum Hall state at $\nu =1/2$ with energy gap up to 6 K, and possible transition from one- to two-component state
• Universal relations between thermoelectrics and noise in mesoscopic transport across a tunnel junction
• Robust translational invariance in topological bands against lattice potentials and disorders
• Sensing the binding and unbinding of anyons at impurities
• Even-denominator fractional quantum Hall states with spontaneously broken rotational symmetry
• Excitation and tunneling spectra of a fractional quantum Hall system in the thin cylinder limit
• Even-denominator fractional quantum Hall states in the zeroth Landau level of ABA trilayer graphene
• Cascade of fractional quantum Hall states in 2D system