Characterization of ferromagnetic $\tau $ -MnAl thin films grown by MBE

ORAL

Abstract

The epitaxial stabilization of MnAl thin films in the $\tau $-phase (tetragonal crystal structure) results in a metallic ferromagnet with a strong uniaxial out-of-plane magnetic anisotropy. The ensuing perpendicular magnetic anisotropy makes these films potentially attractive for energy efficient, high density magnetic memory applications. These thin films are also of contemporary interest for semiconductor spintronics since they can be integrated with III-V semiconductor devices. We describe the epitaxial growth of $\tau $-MnAl films on GaAs (001), as well as the characterization of their structural, magnetic and transport properties. Thin films of $\tau $-MnAl are prepared by molecular beam epitaxy at 250 \textordmasculine C. High-resolution transmission electron microscopy images show a well-ordered crystal while energy dispersive spectroscopy confirms stoichiometric control of the composition. Magnetometry measurements reveal a very high coercivity of 10 kOe, a saturation magnetization of 400 emu/cc and a uniaxial magnetic anisotropy constant $K_{\mathrm{u\thinspace }}=$10 Merg/cc. Further, we demonstrate a route for nanopatterning $\tau $-MnAl films into pillars of sub-100 nm scale diameter.

Authors

  • James Kally

    Pennsylvania State University

  • Scott Cushing

    National Radio Astronomy Observatory, Jodrell Bank Centre for Astrophysics, New York University Abu Dhabi, Naval Research Laboratory, CSIRO Astronomy and Space Sciences, George Mason University, ASTRON, NASA Goddard Space Flight Center, University of Wisconsin-Milwaukee,, Station de radioastronomie de Nancay, Columbia Astrophysics Laboratory, Max-Planck-Institut fur Physik, West Virginia Univ, West Virginia University, Lehigh University, Fraunhofer Institute for Physical Measurement Techniques, Department of Microsystems Engineering (IMTEK), Pennsylvania State University, Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA, Massachusetts Institute of Technology, University of Minnesota, Pennsylvania State Univ, University of Maryland, Towson University, Department of Physics, Villanova University, University of Virginia, Boston University, Univ of Maryland-College Park, Harvard University, The Pennsylvania State Unversity, University of Wisconsin-Madison, McMaster University, California State University - Long Beach, National Chiao Tung University, National Chiao Tung University, Taiwan, Ohio University, University of Rennes, UMR CNRS 6251, Rennes, France, University of Bordeaux, UMR 5804, Floirac, France, University of Bordeaux, UMR 5255, Talence, France, Sandia National laboratories, Livermore, CA, Department of Chemistry, West Virginia University, Morgantwon, WV, The Pennsylvania State University, University of Toronto, Departamento de F\'isica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile, Cinvestav-Unidad Queretaro, Queretaro-76230, Mexico, Department of Physics and Astronomy, West Virginia University, Morgantown, WV-26505-6315, USA, The University of Arizona, TU Dortmund, Dortmund, Naval Air Warfare Center - Aircraft Division

  • Scott Cushing

    National Radio Astronomy Observatory, Jodrell Bank Centre for Astrophysics, New York University Abu Dhabi, Naval Research Laboratory, CSIRO Astronomy and Space Sciences, George Mason University, ASTRON, NASA Goddard Space Flight Center, University of Wisconsin-Milwaukee,, Station de radioastronomie de Nancay, Columbia Astrophysics Laboratory, Max-Planck-Institut fur Physik, West Virginia Univ, West Virginia University, Lehigh University, Fraunhofer Institute for Physical Measurement Techniques, Department of Microsystems Engineering (IMTEK), Pennsylvania State University, Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA, Massachusetts Institute of Technology, University of Minnesota, Pennsylvania State Univ, University of Maryland, Towson University, Department of Physics, Villanova University, University of Virginia, Boston University, Univ of Maryland-College Park, Harvard University, The Pennsylvania State Unversity, University of Wisconsin-Madison, McMaster University, California State University - Long Beach, National Chiao Tung University, National Chiao Tung University, Taiwan, Ohio University, University of Rennes, UMR CNRS 6251, Rennes, France, University of Bordeaux, UMR 5804, Floirac, France, University of Bordeaux, UMR 5255, Talence, France, Sandia National laboratories, Livermore, CA, Department of Chemistry, West Virginia University, Morgantwon, WV, The Pennsylvania State University, University of Toronto, Departamento de F\'isica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile, Cinvestav-Unidad Queretaro, Queretaro-76230, Mexico, Department of Physics and Astronomy, West Virginia University, Morgantown, WV-26505-6315, USA, The University of Arizona, TU Dortmund, Dortmund, Naval Air Warfare Center - Aircraft Division

  • Scott Cushing

    National Radio Astronomy Observatory, Jodrell Bank Centre for Astrophysics, New York University Abu Dhabi, Naval Research Laboratory, CSIRO Astronomy and Space Sciences, George Mason University, ASTRON, NASA Goddard Space Flight Center, University of Wisconsin-Milwaukee,, Station de radioastronomie de Nancay, Columbia Astrophysics Laboratory, Max-Planck-Institut fur Physik, West Virginia Univ, West Virginia University, Lehigh University, Fraunhofer Institute for Physical Measurement Techniques, Department of Microsystems Engineering (IMTEK), Pennsylvania State University, Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA, Massachusetts Institute of Technology, University of Minnesota, Pennsylvania State Univ, University of Maryland, Towson University, Department of Physics, Villanova University, University of Virginia, Boston University, Univ of Maryland-College Park, Harvard University, The Pennsylvania State Unversity, University of Wisconsin-Madison, McMaster University, California State University - Long Beach, National Chiao Tung University, National Chiao Tung University, Taiwan, Ohio University, University of Rennes, UMR CNRS 6251, Rennes, France, University of Bordeaux, UMR 5804, Floirac, France, University of Bordeaux, UMR 5255, Talence, France, Sandia National laboratories, Livermore, CA, Department of Chemistry, West Virginia University, Morgantwon, WV, The Pennsylvania State University, University of Toronto, Departamento de F\'isica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile, Cinvestav-Unidad Queretaro, Queretaro-76230, Mexico, Department of Physics and Astronomy, West Virginia University, Morgantown, WV-26505-6315, USA, The University of Arizona, TU Dortmund, Dortmund, Naval Air Warfare Center - Aircraft Division

  • Scott Cushing

    National Radio Astronomy Observatory, Jodrell Bank Centre for Astrophysics, New York University Abu Dhabi, Naval Research Laboratory, CSIRO Astronomy and Space Sciences, George Mason University, ASTRON, NASA Goddard Space Flight Center, University of Wisconsin-Milwaukee,, Station de radioastronomie de Nancay, Columbia Astrophysics Laboratory, Max-Planck-Institut fur Physik, West Virginia Univ, West Virginia University, Lehigh University, Fraunhofer Institute for Physical Measurement Techniques, Department of Microsystems Engineering (IMTEK), Pennsylvania State University, Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA, Massachusetts Institute of Technology, University of Minnesota, Pennsylvania State Univ, University of Maryland, Towson University, Department of Physics, Villanova University, University of Virginia, Boston University, Univ of Maryland-College Park, Harvard University, The Pennsylvania State Unversity, University of Wisconsin-Madison, McMaster University, California State University - Long Beach, National Chiao Tung University, National Chiao Tung University, Taiwan, Ohio University, University of Rennes, UMR CNRS 6251, Rennes, France, University of Bordeaux, UMR 5804, Floirac, France, University of Bordeaux, UMR 5255, Talence, France, Sandia National laboratories, Livermore, CA, Department of Chemistry, West Virginia University, Morgantwon, WV, The Pennsylvania State University, University of Toronto, Departamento de F\'isica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile, Cinvestav-Unidad Queretaro, Queretaro-76230, Mexico, Department of Physics and Astronomy, West Virginia University, Morgantown, WV-26505-6315, USA, The University of Arizona, TU Dortmund, Dortmund, Naval Air Warfare Center - Aircraft Division

  • Scott Cushing

    National Radio Astronomy Observatory, Jodrell Bank Centre for Astrophysics, New York University Abu Dhabi, Naval Research Laboratory, CSIRO Astronomy and Space Sciences, George Mason University, ASTRON, NASA Goddard Space Flight Center, University of Wisconsin-Milwaukee,, Station de radioastronomie de Nancay, Columbia Astrophysics Laboratory, Max-Planck-Institut fur Physik, West Virginia Univ, West Virginia University, Lehigh University, Fraunhofer Institute for Physical Measurement Techniques, Department of Microsystems Engineering (IMTEK), Pennsylvania State University, Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA, Massachusetts Institute of Technology, University of Minnesota, Pennsylvania State Univ, University of Maryland, Towson University, Department of Physics, Villanova University, University of Virginia, Boston University, Univ of Maryland-College Park, Harvard University, The Pennsylvania State Unversity, University of Wisconsin-Madison, McMaster University, California State University - Long Beach, National Chiao Tung University, National Chiao Tung University, Taiwan, Ohio University, University of Rennes, UMR CNRS 6251, Rennes, France, University of Bordeaux, UMR 5804, Floirac, France, University of Bordeaux, UMR 5255, Talence, France, Sandia National laboratories, Livermore, CA, Department of Chemistry, West Virginia University, Morgantwon, WV, The Pennsylvania State University, University of Toronto, Departamento de F\'isica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile, Cinvestav-Unidad Queretaro, Queretaro-76230, Mexico, Department of Physics and Astronomy, West Virginia University, Morgantown, WV-26505-6315, USA, The University of Arizona, TU Dortmund, Dortmund, Naval Air Warfare Center - Aircraft Division

  • Scott Cushing

    National Radio Astronomy Observatory, Jodrell Bank Centre for Astrophysics, New York University Abu Dhabi, Naval Research Laboratory, CSIRO Astronomy and Space Sciences, George Mason University, ASTRON, NASA Goddard Space Flight Center, University of Wisconsin-Milwaukee,, Station de radioastronomie de Nancay, Columbia Astrophysics Laboratory, Max-Planck-Institut fur Physik, West Virginia Univ, West Virginia University, Lehigh University, Fraunhofer Institute for Physical Measurement Techniques, Department of Microsystems Engineering (IMTEK), Pennsylvania State University, Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA, Massachusetts Institute of Technology, University of Minnesota, Pennsylvania State Univ, University of Maryland, Towson University, Department of Physics, Villanova University, University of Virginia, Boston University, Univ of Maryland-College Park, Harvard University, The Pennsylvania State Unversity, University of Wisconsin-Madison, McMaster University, California State University - Long Beach, National Chiao Tung University, National Chiao Tung University, Taiwan, Ohio University, University of Rennes, UMR CNRS 6251, Rennes, France, University of Bordeaux, UMR 5804, Floirac, France, University of Bordeaux, UMR 5255, Talence, France, Sandia National laboratories, Livermore, CA, Department of Chemistry, West Virginia University, Morgantwon, WV, The Pennsylvania State University, University of Toronto, Departamento de F\'isica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile, Cinvestav-Unidad Queretaro, Queretaro-76230, Mexico, Department of Physics and Astronomy, West Virginia University, Morgantown, WV-26505-6315, USA, The University of Arizona, TU Dortmund, Dortmund, Naval Air Warfare Center - Aircraft Division

  • Scott Cushing

    National Radio Astronomy Observatory, Jodrell Bank Centre for Astrophysics, New York University Abu Dhabi, Naval Research Laboratory, CSIRO Astronomy and Space Sciences, George Mason University, ASTRON, NASA Goddard Space Flight Center, University of Wisconsin-Milwaukee,, Station de radioastronomie de Nancay, Columbia Astrophysics Laboratory, Max-Planck-Institut fur Physik, West Virginia Univ, West Virginia University, Lehigh University, Fraunhofer Institute for Physical Measurement Techniques, Department of Microsystems Engineering (IMTEK), Pennsylvania State University, Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA, Massachusetts Institute of Technology, University of Minnesota, Pennsylvania State Univ, University of Maryland, Towson University, Department of Physics, Villanova University, University of Virginia, Boston University, Univ of Maryland-College Park, Harvard University, The Pennsylvania State Unversity, University of Wisconsin-Madison, McMaster University, California State University - Long Beach, National Chiao Tung University, National Chiao Tung University, Taiwan, Ohio University, University of Rennes, UMR CNRS 6251, Rennes, France, University of Bordeaux, UMR 5804, Floirac, France, University of Bordeaux, UMR 5255, Talence, France, Sandia National laboratories, Livermore, CA, Department of Chemistry, West Virginia University, Morgantwon, WV, The Pennsylvania State University, University of Toronto, Departamento de F\'isica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile, Cinvestav-Unidad Queretaro, Queretaro-76230, Mexico, Department of Physics and Astronomy, West Virginia University, Morgantown, WV-26505-6315, USA, The University of Arizona, TU Dortmund, Dortmund, Naval Air Warfare Center - Aircraft Division

  • Scott Cushing

    National Radio Astronomy Observatory, Jodrell Bank Centre for Astrophysics, New York University Abu Dhabi, Naval Research Laboratory, CSIRO Astronomy and Space Sciences, George Mason University, ASTRON, NASA Goddard Space Flight Center, University of Wisconsin-Milwaukee,, Station de radioastronomie de Nancay, Columbia Astrophysics Laboratory, Max-Planck-Institut fur Physik, West Virginia Univ, West Virginia University, Lehigh University, Fraunhofer Institute for Physical Measurement Techniques, Department of Microsystems Engineering (IMTEK), Pennsylvania State University, Department of Physics and Astronomy, West Virginia University, Morgantown, West Virginia 26506, USA, Massachusetts Institute of Technology, University of Minnesota, Pennsylvania State Univ, University of Maryland, Towson University, Department of Physics, Villanova University, University of Virginia, Boston University, Univ of Maryland-College Park, Harvard University, The Pennsylvania State Unversity, University of Wisconsin-Madison, McMaster University, California State University - Long Beach, National Chiao Tung University, National Chiao Tung University, Taiwan, Ohio University, University of Rennes, UMR CNRS 6251, Rennes, France, University of Bordeaux, UMR 5804, Floirac, France, University of Bordeaux, UMR 5255, Talence, France, Sandia National laboratories, Livermore, CA, Department of Chemistry, West Virginia University, Morgantwon, WV, The Pennsylvania State University, University of Toronto, Departamento de F\'isica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, Chile, Cinvestav-Unidad Queretaro, Queretaro-76230, Mexico, Department of Physics and Astronomy, West Virginia University, Morgantown, WV-26505-6315, USA, The University of Arizona, TU Dortmund, Dortmund, Naval Air Warfare Center - Aircraft Division