Quasiparticle microscope at single quantum hall impurities

Oral-In-person

Abstract

Quantum Hall systems host highly correlated and degenerate electronic states, where exotic quasiparticles such as fractionalized anyons can emerge. However, conventional bulk measurements lack the spatial resolution to probe them individually. Using scanning tunneling spectroscopy (STS) on an ultraclean graphene device under a high magnetic field, we directly visualize quantum Hall quasiparticles in real space near single charged defects. The Coulomb potential of these defects lifts the Landau-level degeneracy, separating orbits with different angular momentum in energy and thereby enabling their individual imaging. When quasiparticles are bound to the impurity potential, distinct spectral features arise, encoding the number and type of bound states. By analyzing the spectral weight, we visualize localized quasiparticles in real space—realizing a quasiparticle microscope that reveals their distribution down to the single-defect limit and opens a pathway to observe and manipulate non-Abelian anyons.

Presenters

  • Yiming Sun

    • Cornell University

Authors

  • Yiming Sun

    • Cornell University
  • Jinghao Deng

    • Lab of Atomic and Solid State Physics, Cornell
  • Dimitri Pimenov

    • Cornell University
  • Kenji Watanabe

    • National Institute for Materials Science
  • Takashi Taniguchi

    • National Institute for Materials Science
  • Erich Mueller

    • Cornell University
  • Xiaomeng Liu

    • Cornell University