Energy Gap Reversal of Prominent Fractional Quantum Hall States in the Second Landau Level

ORAL

Abstract

The fractional quantum Hall effect occurs in high quality two dimensional conductors which have been cooled to low temperatures and placed in strong magnetic fields. A large number of the many-body ground states which emerge in this system are described using Jain's model of non-interacting composite fermions. Yet, in a region of the phase space called the second Landau Level, a number of ground states appear to require descriptions beyond Jain's model. In order to better understand these states, we have explored a little studied region of the second Landau level called the upper spin branch. In this region, we find a new fractional quantum Hall state. Surprisingly, a comparison of this new state and others in this region to counterparts in the lower spin branch reveals a reversal in the relative magnitudes of states' energy gaps. We explore possible explanations of this unusual observation. Measurements at Purdue were funded by the NSF Grant No. DMR-1207375 and the sample growth at Princeton was supported by the Gordon and Betty Moore Foundation through Grant No. GBMF 4420, and by the National Science Foundation MRSEC at the Princeton Center for Complex Materials.

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Authors

  • Ethan Kleinbaum

    Purdue University

  • Matt Bowers

    University of Notre Dame, University of Bari, Gran Sasso Science Institute, JINA and UND, UTK, LLNL, OU, INFN, TAMU, Universidad Complutense, Madrid, Lawrence Livermore National Laboratory, Division of Nuclear Physics, National Centre for Nuclear Research, Warsaw, Notre Dame University, University of Michigan, Michigan State University, Univ of Notre Dame, Weizmann Institute, Univ of Birmingham, Univ of Michigan, Oak Ridge National Laboratory, Argonne National Laboratory, The Hebrew University Jerusalem, Indiana University Purdue University Fort Wayne, Professor, University of Notre Dame, Assistant Professor, University of Notre Dame, PhD student, Associate Professor, University of Notre Dame, University of Richmond, University of Surrey, University of Richmond, University of Oslo, University of Wisconsin-La Crosse, University of Notre Dame, Department of Civil Engineering, University of Notre Dame, Department of Applied Computational Mathematics and Statistics, IUPUI Department of Physics, Indianapolis, IN, Ohio Northern University, Northern Kentucky University, Physics Department, Unversity of Missouri, Physics Department, REU Summer Intern, Sichuan University, Purdue University, Princeton University, Monmouth College, ETH, Switzerland, EPFL, Switzerland, Institut Laue-Langevin, France, Kent State University, University of Tennessee, Indiana University South Bend, University Of Notre Dame

  • Matt Bowers

    University of Notre Dame, University of Bari, Gran Sasso Science Institute, JINA and UND, UTK, LLNL, OU, INFN, TAMU, Universidad Complutense, Madrid, Lawrence Livermore National Laboratory, Division of Nuclear Physics, National Centre for Nuclear Research, Warsaw, Notre Dame University, University of Michigan, Michigan State University, Univ of Notre Dame, Weizmann Institute, Univ of Birmingham, Univ of Michigan, Oak Ridge National Laboratory, Argonne National Laboratory, The Hebrew University Jerusalem, Indiana University Purdue University Fort Wayne, Professor, University of Notre Dame, Assistant Professor, University of Notre Dame, PhD student, Associate Professor, University of Notre Dame, University of Richmond, University of Surrey, University of Richmond, University of Oslo, University of Wisconsin-La Crosse, University of Notre Dame, Department of Civil Engineering, University of Notre Dame, Department of Applied Computational Mathematics and Statistics, IUPUI Department of Physics, Indianapolis, IN, Ohio Northern University, Northern Kentucky University, Physics Department, Unversity of Missouri, Physics Department, REU Summer Intern, Sichuan University, Purdue University, Princeton University, Monmouth College, ETH, Switzerland, EPFL, Switzerland, Institut Laue-Langevin, France, Kent State University, University of Tennessee, Indiana University South Bend, University Of Notre Dame

  • Matt Bowers

    University of Notre Dame, University of Bari, Gran Sasso Science Institute, JINA and UND, UTK, LLNL, OU, INFN, TAMU, Universidad Complutense, Madrid, Lawrence Livermore National Laboratory, Division of Nuclear Physics, National Centre for Nuclear Research, Warsaw, Notre Dame University, University of Michigan, Michigan State University, Univ of Notre Dame, Weizmann Institute, Univ of Birmingham, Univ of Michigan, Oak Ridge National Laboratory, Argonne National Laboratory, The Hebrew University Jerusalem, Indiana University Purdue University Fort Wayne, Professor, University of Notre Dame, Assistant Professor, University of Notre Dame, PhD student, Associate Professor, University of Notre Dame, University of Richmond, University of Surrey, University of Richmond, University of Oslo, University of Wisconsin-La Crosse, University of Notre Dame, Department of Civil Engineering, University of Notre Dame, Department of Applied Computational Mathematics and Statistics, IUPUI Department of Physics, Indianapolis, IN, Ohio Northern University, Northern Kentucky University, Physics Department, Unversity of Missouri, Physics Department, REU Summer Intern, Sichuan University, Purdue University, Princeton University, Monmouth College, ETH, Switzerland, EPFL, Switzerland, Institut Laue-Langevin, France, Kent State University, University of Tennessee, Indiana University South Bend, University Of Notre Dame

  • Matt Bowers

    University of Notre Dame, University of Bari, Gran Sasso Science Institute, JINA and UND, UTK, LLNL, OU, INFN, TAMU, Universidad Complutense, Madrid, Lawrence Livermore National Laboratory, Division of Nuclear Physics, National Centre for Nuclear Research, Warsaw, Notre Dame University, University of Michigan, Michigan State University, Univ of Notre Dame, Weizmann Institute, Univ of Birmingham, Univ of Michigan, Oak Ridge National Laboratory, Argonne National Laboratory, The Hebrew University Jerusalem, Indiana University Purdue University Fort Wayne, Professor, University of Notre Dame, Assistant Professor, University of Notre Dame, PhD student, Associate Professor, University of Notre Dame, University of Richmond, University of Surrey, University of Richmond, University of Oslo, University of Wisconsin-La Crosse, University of Notre Dame, Department of Civil Engineering, University of Notre Dame, Department of Applied Computational Mathematics and Statistics, IUPUI Department of Physics, Indianapolis, IN, Ohio Northern University, Northern Kentucky University, Physics Department, Unversity of Missouri, Physics Department, REU Summer Intern, Sichuan University, Purdue University, Princeton University, Monmouth College, ETH, Switzerland, EPFL, Switzerland, Institut Laue-Langevin, France, Kent State University, University of Tennessee, Indiana University South Bend, University Of Notre Dame