Cr<sub>5</sub>Te<sub>8</sub>/WSe<sub>2</sub> heterostructures by van der Waals epitaxy

ORAL

Abstract

Recently, two-dimensional (2D) van der Waals (vdW) heterostructures enable the exploration of new physics and applications. Many reported 2D heterostructures are formed by exfoliation and restacking of 2D flakes of small sizes and are restricted to vdW materials. In this work, we report epitaxial growth of covalent 2D magnet Cr5Te8 on vdW semiconducting monolayer WSe2 template, with a tunable thickness down to a single unit cell, via two-step chemical vapor deposition. Moiré superlattices were clearly identified by high-resolution scanning transmission electron microscopy images. Strong coupling between Cr5Te8 and WSe2 was demonstrated by the reduction of the Cr valence state near the interface and strong quenching of the photoluminescence of WSe2, which is expected to be absent in fully vdW heterostructures. Ferromagnetism in 2D Cr5Te8 crystals down to two unit cells thicknesses was measured by both reflective magnetic circular dichroism and X-ray magnetic circular dichroism. Rich magnetic domain patterns were identified by photoemission electron microscopy. Our work expands 2D heterostructures into covalent material systems.

*Work is supported by NSF ECCS-2042085, NSF MRI-1229208, China Postdoctoral Science Foundation (2020M670042). Work at Bryn Mawr College is supported by NSF DMR-1708790.

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Presenters

  • Mengying Bian

    • University at Buffalo, State University of New York

Authors

  • Mengying Bian

    • University at Buffalo, State University of New York

  • Liang Zhu

    • Southern University of Science and Technology
    • Department of Physics and Shenzhen Key Laboratory for Advanced Quantum Functional Materials and Devices, Southern University of Science and Technology, China

  • Xiao Wang

    • Bryn Mawr College

  • Junho Choi

    • Los Alamos National Laboratory

  • Rajesh V Chopdekar

    • Lawrence Berkeley National Laboratory

  • Sichen Wei

    • University at Buffalo, State University of University

  • Lishu Wu

    • Nanyang Technological University

  • Chang Huai

    • University at Buffalo, State University of New York
    • State Univ of NY - Buffalo

  • Austin Marga

    • University at Buffalo, State University of New York
    • SUNY Buffalo

  • Fei Yao

    • University at Buffalo, State University of New York

  • Ting Yu

    • Nanyang Technological University

  • Scott A Crooker

    • Los Alamos Natl Lab
    • National High Magnetic Field Laboratory, Los Alamos

  • Xuemei Cheng

    • Bryn Mawr College

  • Renat Sabirianov

    • University of Nebraska - Omaha

  • Gang Wang

    • Southern University of Science and Technology
    • Department of Physics and Shenzhen Key Laboratory for Advanced Quantum Functional Materials and Devices, Southern University of Science and Technology, China
    • Department of Physics, Southern University of Science and Technology, Shenzhen 518055, China

  • Yanglong Hou

    • Peking University

  • Hao Zeng

    • State Univ of NY - Buffalo
    • SUNY Buffalo