Measuring the Superconducting Energy Gaps of Doped Iron Pnictide Superconductors Ba_(1-x) K_x Fe_2 A_2 using Soft Point Contact Spectroscopy

POSTER

Abstract

The iron-based superconductors or iron pnictides provide a new platform where the phenomenon of multi-band superconductivity can be studied. Multiple energy gaps in these samples can be measured, depending on the way the crystal has been grown and how the tunneling directions are accessed through fabrication and the way electrical contacts are made. These energy gaps are anisotropic relative to the crystal lattice, with some gaps primarily conducting parallel or perpendicular to the c-axis of the lattice. In this presentation, we report ongoing measurements of the energy gaps of K-doped iron pnictide Ba(1-x)KxFe2As2 superconductors, where x = 0.6, 0.5, and 0.33 near liquid helium temperatures. We report the observation of peaks and broad shoulders; some correlate well with existing data from literature while other new peaks are unexplained. These measurements have been performed fully by undergraduates.

Authors

  • Oberon Wackwitz

    University of the Sciences

  • Luke Conover

    University of the Sciences

  • Caitlyn McConnell

    University of the Sciences

  • Debbie Andres

    Department of Applied Physics and Department of Physics, Columbia University, Istituto Italiano di Tecnologia, Graphene Labs, Italy, Department of Physics and Astronomy, Purdue University, Department of Electrical Engineering, Princeton University, Department of Applied Physics and Applied Mathematics, Columbia University, NJIT, New Jersey Inst of Technology, New Jersey Inst of Tech, New Jersey Institute of Technology, Center for Advanced Radiation Sources, University of Chicago, High Pressure Science and Technology Advanced Research, State University of New York at Stony Brook, Rutgers University, NIST, Brookhaven National Laboratory, University of Chicago, University of South Florida, ETH Zurich, Max Planck POSTECH/Korea Research Initiative, University of Virginia, Rutgers University - Camden, New Jersey Institute of technology, Shaanxi Normal University, Pohang Science and Technology University, Sungkyunkwan University, Northern Illinois University and Argonne National Laboratory, Beijing National Laboratory for Condensed Matter Physics , and Institute of Physics, Chinese Academy of Sciences, Rutgers U., Orsova Engineers, U.S. Naval Research Laboratory, Center for Space Science and Engineering Research, Virginia Tech, Virginia., Princeton University, NASA Goddard Space Flight Center, Villanova University, SOFIA/USRA, Jet Propulsion Laboratory, Hudson Regional Health Commision, Rutgers University, College of William & Mary, Department of Physics, Drexel University, Drexel University, Drexel Universty, University of Massachusetts Amherst, Pohang Institue of Science and Technology, Indiana University - Purdue University Indianapolis, Department of Physics, University of Maryland, Naval Research Laboratory, Towson Univ, Rice University, Independence Blue Cross Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, Department of Physics, Temple University, PulseTorr LLC, Department of Chemistry, West Chester University, Department of Physics, West Chester University, College of William and Mary Dept. of Physics, University of Virginia Dept. of Materials Science and Engineering, United States Naval Academy, Rutgers The State University of New Jersey, Univ of Maryland-College Park, Los Alamos National Laboratory, POSTECH, New Jersey Institute of Technology, Department of Electrical and Computer Engineering, HamSCI/ARRL, Virginia Tech, Rutgers University-Camden, University of Washington, Rutgers, The State University of New Jersey

  • Debbie Andres

    Department of Applied Physics and Department of Physics, Columbia University, Istituto Italiano di Tecnologia, Graphene Labs, Italy, Department of Physics and Astronomy, Purdue University, Department of Electrical Engineering, Princeton University, Department of Applied Physics and Applied Mathematics, Columbia University, NJIT, New Jersey Inst of Technology, New Jersey Inst of Tech, New Jersey Institute of Technology, Center for Advanced Radiation Sources, University of Chicago, High Pressure Science and Technology Advanced Research, State University of New York at Stony Brook, Rutgers University, NIST, Brookhaven National Laboratory, University of Chicago, University of South Florida, ETH Zurich, Max Planck POSTECH/Korea Research Initiative, University of Virginia, Rutgers University - Camden, New Jersey Institute of technology, Shaanxi Normal University, Pohang Science and Technology University, Sungkyunkwan University, Northern Illinois University and Argonne National Laboratory, Beijing National Laboratory for Condensed Matter Physics , and Institute of Physics, Chinese Academy of Sciences, Rutgers U., Orsova Engineers, U.S. Naval Research Laboratory, Center for Space Science and Engineering Research, Virginia Tech, Virginia., Princeton University, NASA Goddard Space Flight Center, Villanova University, SOFIA/USRA, Jet Propulsion Laboratory, Hudson Regional Health Commision, Rutgers University, College of William & Mary, Department of Physics, Drexel University, Drexel University, Drexel Universty, University of Massachusetts Amherst, Pohang Institue of Science and Technology, Indiana University - Purdue University Indianapolis, Department of Physics, University of Maryland, Naval Research Laboratory, Towson Univ, Rice University, Independence Blue Cross Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, Department of Physics, Temple University, PulseTorr LLC, Department of Chemistry, West Chester University, Department of Physics, West Chester University, College of William and Mary Dept. of Physics, University of Virginia Dept. of Materials Science and Engineering, United States Naval Academy, Rutgers The State University of New Jersey, Univ of Maryland-College Park, Los Alamos National Laboratory, POSTECH, New Jersey Institute of Technology, Department of Electrical and Computer Engineering, HamSCI/ARRL, Virginia Tech, Rutgers University-Camden, University of Washington, Rutgers, The State University of New Jersey

  • Debbie Andres

    Department of Applied Physics and Department of Physics, Columbia University, Istituto Italiano di Tecnologia, Graphene Labs, Italy, Department of Physics and Astronomy, Purdue University, Department of Electrical Engineering, Princeton University, Department of Applied Physics and Applied Mathematics, Columbia University, NJIT, New Jersey Inst of Technology, New Jersey Inst of Tech, New Jersey Institute of Technology, Center for Advanced Radiation Sources, University of Chicago, High Pressure Science and Technology Advanced Research, State University of New York at Stony Brook, Rutgers University, NIST, Brookhaven National Laboratory, University of Chicago, University of South Florida, ETH Zurich, Max Planck POSTECH/Korea Research Initiative, University of Virginia, Rutgers University - Camden, New Jersey Institute of technology, Shaanxi Normal University, Pohang Science and Technology University, Sungkyunkwan University, Northern Illinois University and Argonne National Laboratory, Beijing National Laboratory for Condensed Matter Physics , and Institute of Physics, Chinese Academy of Sciences, Rutgers U., Orsova Engineers, U.S. Naval Research Laboratory, Center for Space Science and Engineering Research, Virginia Tech, Virginia., Princeton University, NASA Goddard Space Flight Center, Villanova University, SOFIA/USRA, Jet Propulsion Laboratory, Hudson Regional Health Commision, Rutgers University, College of William & Mary, Department of Physics, Drexel University, Drexel University, Drexel Universty, University of Massachusetts Amherst, Pohang Institue of Science and Technology, Indiana University - Purdue University Indianapolis, Department of Physics, University of Maryland, Naval Research Laboratory, Towson Univ, Rice University, Independence Blue Cross Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, Department of Physics, Temple University, PulseTorr LLC, Department of Chemistry, West Chester University, Department of Physics, West Chester University, College of William and Mary Dept. of Physics, University of Virginia Dept. of Materials Science and Engineering, United States Naval Academy, Rutgers The State University of New Jersey, Univ of Maryland-College Park, Los Alamos National Laboratory, POSTECH, New Jersey Institute of Technology, Department of Electrical and Computer Engineering, HamSCI/ARRL, Virginia Tech, Rutgers University-Camden, University of Washington, Rutgers, The State University of New Jersey

  • Debbie Andres

    Department of Applied Physics and Department of Physics, Columbia University, Istituto Italiano di Tecnologia, Graphene Labs, Italy, Department of Physics and Astronomy, Purdue University, Department of Electrical Engineering, Princeton University, Department of Applied Physics and Applied Mathematics, Columbia University, NJIT, New Jersey Inst of Technology, New Jersey Inst of Tech, New Jersey Institute of Technology, Center for Advanced Radiation Sources, University of Chicago, High Pressure Science and Technology Advanced Research, State University of New York at Stony Brook, Rutgers University, NIST, Brookhaven National Laboratory, University of Chicago, University of South Florida, ETH Zurich, Max Planck POSTECH/Korea Research Initiative, University of Virginia, Rutgers University - Camden, New Jersey Institute of technology, Shaanxi Normal University, Pohang Science and Technology University, Sungkyunkwan University, Northern Illinois University and Argonne National Laboratory, Beijing National Laboratory for Condensed Matter Physics , and Institute of Physics, Chinese Academy of Sciences, Rutgers U., Orsova Engineers, U.S. Naval Research Laboratory, Center for Space Science and Engineering Research, Virginia Tech, Virginia., Princeton University, NASA Goddard Space Flight Center, Villanova University, SOFIA/USRA, Jet Propulsion Laboratory, Hudson Regional Health Commision, Rutgers University, College of William & Mary, Department of Physics, Drexel University, Drexel University, Drexel Universty, University of Massachusetts Amherst, Pohang Institue of Science and Technology, Indiana University - Purdue University Indianapolis, Department of Physics, University of Maryland, Naval Research Laboratory, Towson Univ, Rice University, Independence Blue Cross Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, Department of Physics, Temple University, PulseTorr LLC, Department of Chemistry, West Chester University, Department of Physics, West Chester University, College of William and Mary Dept. of Physics, University of Virginia Dept. of Materials Science and Engineering, United States Naval Academy, Rutgers The State University of New Jersey, Univ of Maryland-College Park, Los Alamos National Laboratory, POSTECH, New Jersey Institute of Technology, Department of Electrical and Computer Engineering, HamSCI/ARRL, Virginia Tech, Rutgers University-Camden, University of Washington, Rutgers, The State University of New Jersey

  • Roberto Ramos

    University of the Sciences