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