Observation of room-temperature polar skyrmions in oxide superlattice

ORAL

Abstract

Recent discovery of polarization flux closures, vortices and skyrmions in polar oxide superlattices suggests the presence of a complex, multi-dimensional system capable of exotic physical responses[i],[ii],[iii], where the exploration of novel emergent phenomena and exotic phases in condensed-matter physics is greatly facilitated. Here, we have observed a room-temperature polar skyrmions in a PbTiO3/SrTiO3 superlattices grown on SrTiO3(001) substrate. X-Ray diffraction and large scale scanning transmission electron microscopy imaging confirmed the present of the polar skyrmions phase. In addition, phase-field modeling and second-principles calculations reveal that the polar skyrmions have a skyrmion number of +1. Moreover, special uniform chirality was revealed by resonant soft X-ray diffraction experiments showing obvious circular dichroism. Such nanometer-scale polar skyrmions are the electric analogs of magnetic skyrmions, and could advance ferroelectrics towards new levels of functionality.
[i] Das, S., Tang, Y. L. et. al, Nature (under reviw)；[ii] Yadav, A. K. et. al, Nature 530, 198-201 (2016).；[iii] Shafer, P., García-Fernández. P. et al., Proc. Natl. Acad. Sci. USA 115, 915 (2018).

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Presenters

  • YUNLONG TANG

    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.

Authors

  • YUNLONG TANG

    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.

  • Sujit Das

    • Department of Materials Science and Engineering, University of California at Berkeley
    • Department of Materials Science & Engineering, University of California, Berkeley
    • University of California, Berkeley
    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.
    • Physics Department, Univesity of California, Berkeley

  • Zijian Hong

    • The Pennsylvania State University, University Park, Pennsylvania 16802, USA

  • M. A. P. Gonçalves

    • Luxembourg Institute of Science and Technology (LIST), 5 avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxemburg.

  • Margaret McCarter

    • Department of Physics, University of California, Berkeley
    • University of California, Berkeley
    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.

  • Christoph Klewe

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

  • F. Gómez-Ortiz

    • Universidad de Cantabria, Cantabria Campus Internacional, Avenidad de los Castros s/n, E-39005 Santander, Spain.

  • Padraic Shafer

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

  • Elke Arenholz

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

  • Vladimir A Stoica

    • The Pennsylvania State University, University Park, Pennsylvania 16802, USA

  • Shang-Lin Hsu

    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.

  • B. Wang

    • The Pennsylvania State University, University Park, Pennsylvania 16802, USA

  • Colin Ophus

    • Molecular Foundry, Lawrence Berkeley National Laboratory
    • Lawrence Berkeley National Laboratory

  • J. F. Liu

    • Lawrence Berkeley National Laboratory

  • Christopher Nelson

    • Oak Ridge National Laboratory, Bethel Valley Rd., Tennessee 37831-6071, USA
    • Oak Ridge National Laboratory

  • Sahar Saremi

    • University of California, Berkeley
    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.
    • Materials Science and Engineering, University of California, Berkeley
    • Department of Materials Science and Engineering, University of California, Berkeley

  • Bhagwati Prasad

    • University of California, Berkeley
    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.
    • Physics Department, Univesity of California, Berkeley
    • Department of Materials Science and Engineering, University of California, Berkeley

  • Darrell G. Schlom

    • Cornell University
    • Cornell University, Ithaca, New York 14853, USA
    • Department of Materials Science and Engineering, Cornell University
    • Department of Materials Science and Engineering, Kavli Institute at Cornell for Nanoscale Science, Cornell University
    • Materials Science & Engineering, Cornell University
    • Department of Materials Science and Engineering,, Cornell University
    • Materials Science and Engineering, University of Cornell

  • A. B. Mei

    • Cornell University, Ithaca, New York 14853, USA

  • Jorge Iniguez

    • LIST
    • Luxembourg Institute of Science and Technology (LIST), 5 avenue des Hauts-Fourneaux, L-4362 Esch/Alzette, Luxemburg.

  • Pablo Garcia-Fernandez

    • Universidad de Cantabria, Cantabria Campus Internacional, Avenidad de los Castros s/n, E-39005 Santander, Spain.

  • Long Q. Chen

    • The Pennsylvania State University, University Park, Pennsylvania 16802, USA

  • Javier Junquera

    • University of Cantabria
    • Departmento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria
    • Departamento de Ciencias de la Tierra y Física de la Materia Condensada, Universidad de Cantabria, Cantabria Campus Internacional, Avenidad de los Castros s/n, E-39005 Santan
    • Universidad de Cantabria, Cantabria Campus Internacional, Avenidad de los Castros s/n, E-39005 Santander, Spain.

  • Lane Martin

    • Department of Materials Science & Engineering, University of California, Berkeley
    • University of California, Berkeley
    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.
    • Materials Science and Engineering, University of California, Berkeley
    • University of Illinois at Urbana-Champaign

  • R Ramesh

    • Department of Physics, University of California Berkeley, California, USA
    • Department of Materials Science and Engineering, University of California at Berkeley
    • Department of Materials Science and Engineering, University of California, Berkeley, California 94720, USA.
    • Department of Materials Science and Engineering, University of California, Berkeley
    • Department of Physics, University of California, Berkeley