Artificial two-dimensional polar metal at room temperature

ORAL

Abstract

Polar metals, commonly defined by the coexistence of polar crystal structure and metallicity, are thought to be scarce because the long-range electrostatic fields favoring the polar structure are expected to be fully screened by the conduction electrons of a metal. Moreover, reducing from three to two dimensions, it remains an open question whether a polar metal can exist. Here, we report on the realization of a room temperature two-dimensional polar metal of the B-site type in tri-color (tri-layer) superlattices BaTiO3/SrTiO3 /LaTiO3. A combination of atomic resolution scanning transmission electron microscopy (STEM) with electron energy loss spectroscopy (EELS), optical second harmonic generation (SHG), electrical transport, and first-principles calculations have revealed the microscopic mechanisms of periodic electric polarization, charge distribution, and orbital symmetry. Our results provide a route to a new class of all-oxide artificial non-centrosymmetric quasi-two-dimensional metals with exotic quantum states including coexisting ferroelectric, ferromagnetic, and superconducting phases.

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Presenters

  • Yanwei Cao

    • Rutgers University
    • Department of Physics & Astronomy, Rutgers the State Univ of NJ New Brunswick
    • Department of Physics, Ningbo Institute of Materials Technology and Engineering

Authors

  • Yanwei Cao

    • Rutgers University
    • Department of Physics & Astronomy, Rutgers the State Univ of NJ New Brunswick
    • Department of Physics, Ningbo Institute of Materials Technology and Engineering

  • Zhen Wang

    • Department of Physcis and Astronomy, Louisiana State University
    • Louisiana State University
    • Louisiana State Univ - Baton Rouge
    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory
    • Department of Physics and Astronomy, Louisiana State University

  • Se Young Park

    • University of California Berkeley
    • Physics, University of California, Berkeley

  • Yakun Yuan

    • Pennsylvania State University

  • Xiaoran Liu

    • Rutgers University
    • Department of Physics & Astronomy, Rutgers the State Univ of NJ New Brunswick

  • S. Nikitin

    • Pennsylvania State University

  • H. Akamatsu

    • Pennsylvania State University
    • Institute for Materials Chemistry and Engineering, Kyushu University

  • Mikhail Kareev

    • Rutgers University
    • Department of Physics, Rutgers Univ
    • Physics and Astronomy, Rutgers University

  • Srimanta Middey

    • University of Arkansas

  • Derek Meyers

    • Brookhaven National Laboratory
    • Condensed Matter Physics and Materials Science, Brookhaven National Laboratory
    • Brookhaven Natl Lab

  • P. Thompson

    • European Synchrotron Radiation Facility

  • Philip Ryan

    • Argonne National Laboratory
    • Argonne National Labs

  • Padraic Shafer

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

  • Alpha N'Diaye

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

  • Elke Arenholz

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

  • V. Gopalan

    • Pennsylvania State University

  • Yimei Zhu

    • Condensed Matter Physcis and Materials Science Departement, Brookhaven National Laboratory
    • Brookhaven National Laboratory
    • Condensed Matter Physics & Materials Science, Brookhaven National Laboratory
    • Brookhaven Natl Lab
    • Brookhaven National Lab
    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory
    • Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory
    • Condensed Matter Physics & Materials Science Department, Brookhaven National Laboratory

  • Karin Rabe

    • Rutgers University
    • Physics and Astronomy, Rutgers University

  • Jak Chakhalian

    • Rutgers University
    • Department of Physics & Astronomy, Rutgers the State Univ of NJ New Brunswick
    • Department of Physics, Rutgers Univ
    • Physics and Astronomy, Rutgers University