title: Observation of a nematic quantum Hall liquid on the surface of bismuth.
abstract: Nematic quantum fluids with wave functions that break the underlying crystalline symmetry can form in interacting electronic systems. We examined the quantum Hall states that arise in high magnetic fields from anisotropic hole pockets on the Bi(111) surface. Spectroscopy performed with a scanning tunneling microscope showed that a combination of single-particle effects and many-body Coulomb interactions lift the six-fold Landau level (LL) degeneracy to form three valley-polarized quantum Hall states. We imaged the resulting anisotropic LL wave functions and found that they have a different orientation for each broken-symmetry state. The wave functions correspond to those expected from pairs of hole valleys and provide a direct spatial signature of a nematic electronic phase.
authors.affiliation: Joseph Henry Laboratories and Department of Physics, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Benjamin E
authors.initials: BE
authors.lastname: Feldman
authors.affiliation: Joseph Henry Laboratories and Department of Physics, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Mallika T
authors.initials: MT
authors.lastname: Randeria
authors.affiliation: Joseph Henry Laboratories and Department of Physics, Princeton University, Princeton, NJ 08544, USA.
authors.forename: András
authors.initials: A
authors.lastname: Gyenis
authors.affiliation: Department of Physics, University of Texas, Austin, TX 78712, USA.
authors.forename: Fengcheng
authors.initials: F
authors.lastname: Wu
authors.affiliation: Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Huiwen
authors.initials: H
authors.lastname: Ji
authors.affiliation: Department of Chemistry, Princeton University, Princeton, NJ 08544, USA.
authors.forename: R J
authors.initials: RJ
authors.lastname: Cava
authors.affiliation: Department of Physics, University of Texas, Austin, TX 78712, USA.
authors.forename: Allan H
authors.initials: AH
authors.lastname: MacDonald
authors.affiliation: Joseph Henry Laboratories and Department of Physics, Princeton University, Princeton, NJ 08544, USA. yazdani@princeton.edu.
authors.forename: Ali
authors.initials: A
authors.lastname: Yazdani