Structural phase diagram of doped HfO<sub>2</sub> bulk single crystal

ORAL

Abstract

HfO2-based materials attract a lot of research interest because the rich polymorphism, including several metastable phases, results in intriguing physics properties and potential for applications. However, the absence of certain phases in the bulk sample hinders a deeper understanding. Here, we report that the high-quality HfO2 single crystals have been successfully grown by a state-of-the-art laser-diode-heated floating zone (LDFZ) technique. Metastable phases have been stabilized, which is sensitive to dopants and thermal treatments. X-ray, TEM, and neutron diffraction are performed for a comprehensive structural phase diagram. DFT calculations elucidate the energy paths of phase formation and emphasize the crucial factors in the stabilization of metastable phases. Our study of bulk HfO2 single crystals uniquely unveils the rich structural physics, including domain and domain wall nature, and paves a new essential road for future study of HfO2-based materials.

*The experimental work was performed at the center for Quantum Materials Synthesis (cQMS), funded by the Gordon and Betty Moore Foundation's EPiQS initiative through grant GBMF6402, and by Rutgers University. Y.Q., S.S., and K.M.R. were supported by the Office of Naval Research Grant N00014-17-1-2770.

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Presenters

  • Xianghan Xu

    • Department of Physics and Astronomy, Rutgers University-New Brunswick
    • Rutgers, The State University of New Jersey
    • Department of Physics and Astronomy, Rutgers University

Authors

  • Xianghan Xu

    • Department of Physics and Astronomy, Rutgers University-New Brunswick
    • Rutgers, The State University of New Jersey
    • Department of Physics and Astronomy, Rutgers University

  • Fei-Ting Huang

    • Rutgers, The State University of New Jersey

  • Yubo Qi

    • Rutgers University, New Brunswick
    • Rutgers, The State University of New Jersey

  • Sobhit Singh

    • Rutgers, The State University of New Jersey
    • Department of Physics and Astronomy, Rutgers University
    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, USA

  • Karin M Rabe

    • Rutgers University, New Brunswick
    • Rutgers, The State University of New Jersey
    • Dept. of Physics and Astronomy, Rutgers University, New Brunswick
    • Department of Physics and Astronomy, Rutgers University, Piscataway, NJ, USA

  • Dimuthu Obeysekera

    • New Jersey Institute of Technology
    • Physics, NJ Institute of Technology

  • Junjie Yang

    • New Jersey Institute of Technology
    • Physics, NJ Institute of Technology
    • New Jersey Inst of Tech
    • Department of Physics, New Jersey Institute of Technology

  • M.-W. Chu

    • National Taiwan University

  • Sang-Wook Cheong

    • Rutgers University, New Brunswick
    • Department of Physics and Astronomy, Rutgers University-New Brunswick
    • Rutgers Center for Emergent Materials, Rutgers University
    • Rutgers, The State University of New Jersey
    • Rutgers University
    • Department of Physics and Astronomy, Rutgers University
    • Center for Quantum Materials Synthesis, Rutgers University
    • Center for Emergent Materials and Department of Physics and Astronomy, Rutgers