Ultralow Damping in Epitaxial Spinel Ferrite Thin Films

ORAL

Abstract

Magnetic insulator thin films are expected to be excellent media for spin-based information without charge flow. This expectation relies on the premise that magnetic insulators exhibit lower magnetic damping compared to their metallic counterparts. However, insulating behavior is not a sufficient requirement for low damping, as evidenced by the very limited options for low-damping magnetic insulators. In this presentation, we demonstrate a new class of ultralow-damping insulator based on design criteria minimizing orbital angular momentum as well as crystalline and cation valence disorder. Specifically, we show ultralow damping in spinel structure magnesium aluminum ferrite (MAFO), in which magnetization arises solely from Fe3+ ions with zero orbital angular momentum. Epitaxial MAFO films with thicknesses <20 nm exhibit ferromagnetic resonance linewidths of ≈0.6 mT around 10 GHz and Gilbert damping parameters of ≈0.0015. Our findings demonstrate that minimal spin-orbit coupling and coherent epitaxy allow for ultralow damping in ferrite thin films, expanding the materials choices for energy-efficient insulator spintronics.

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Presenters

  • Satoru Emori

    • Physics, Virginia Polytechnic Institute and State University
    • Virginia Tech

Authors

  • Satoru Emori

    • Physics, Virginia Polytechnic Institute and State University
    • Virginia Tech

  • Di Yi

    • Stanford Univ
    • Applied Physics, Stanford University
    • Stanford University

  • Samuel Crossley

    • Department of Applied Physics, Stanford University
    • Applied Physics, Stanford University
    • Stanford University

  • Jacob Wisser

    • Applied Physics, Stanford University
    • Stanford University

  • Purnima Balakrishnan

    • Stanford University

  • Padraic Shafer

    • Lawrence Berkeley National Laboratory
    • Advanced Light Source, Lawrence Berkeley National Laboratory
    • Advanced Light Source

  • Christoph Klewe

    • Advanced Light Source
    • Lawrence Berkeley National Laboratory

  • Alpha N'Diaye

    • Lawrence Berkeley National Laboratory
    • Lawrence Berkeley Natl Lab
    • Advanced Light Source
    • Advanced Light Source, Lawrence Berkeley National Laboratory

  • Brittany Urwin

    • Air Force Research Laboratory

  • Krishnamurthy Mahalingam

    • Air Force Research Laboratory

  • Brandon Howe

    • Air Force Research Laboratory

  • Harold Hwang

    • Geballe Laboratory for Advanced Materials, Department of Applied Physics, Stanford University, Stanford, CA, United States, Stanford Institute for Materials and Energy Science
    • Department of Applied Physics, Stanford University
    • Department of Applied Physics, Geballe Laboratory for Advanced Materials, Stanford Institute for Materials and Energy Sciences, Stanford University, SLAC National Accelerator
    • Applied Physics, Stanford University
    • Stanford Univ
    • Stanford University
    • Stanford Univeristy

  • Elke Arenholz

    • Lawrence Berkeley National Laboratory
    • Advanced Light Source, Lawrence Berkeley National Laboratory
    • Advance Light Source, Lawrence Berkeley National Laboratory
    • Advanced Light Source

  • Yuri Suzuki

    • Applied Physics, Stanford University
    • Stanford Univ
    • Stanford University