Functional Properties at Domain Walls in BiFeO$_{3}$: Electrical, Magnetic, and Structural investigations

ORAL

Abstract

BiFeO$_{3}$ (BFO) is a widely studied robust ferroelectric, antiferromagnetic multiferroic. Conducting-atomic force microscopy studies reveal the presence of enhanced conductivity at certain types of domain walls in BFO. We have completed detailed TEM studies of the physical structure at these domain walls as well as in-depth DFT calculations of the evolution of electronic structure at these domain walls. These studies reveal two major contributions to the observed conduction: the formation of an electrostatic potential at the domain walls as well as a structurally-driven change in the electronic structure (i.e., a lower band gap locally) at the domain walls. We will discuss the use of optical characterization techniques as a way of probing this change in electronic structure at domain walls as well as detailed IV characterization both in atmospheric and UHV environments. Finally, the evolution of magnetism at these domain walls has been studied through the use of photoemission measurements. Initial findings point to a significant change in the magnetic order at these domain walls in BFO.

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Authors

  • Qing He

    Department of Physics, UC Berkeley

  • C.-H. Yang

    Department of Physics, and Material Science and Engineering, University of California, Berkeley, CA 94720, USA., Department of Physics, UC Berkeley

  • P. Yu

    Department of Physics, UC Berkeley

  • M. Gajek

    University of Califonia at Berkeley, Department of Physics, and Material Science and Engineering, University of California, Berkeley, CA 94720, USA., Department of Physics, UC Berkeley

  • J. Seidel

    University of Califonia at Berkeley, UC Berkeley, UC Santa Barbara, University of Cambridge, FZ Dresden-Rossendorf, Germany, Oakridge National Lab, Lawrence Berkeley National Lab, TU Dresden, Germany, National Chiao Tung University, Taiwan, Department of Physics, and Material Science and Engineering, University of California, Berkeley, CA 94720, USA., Department of Physics, UC Berkeley

  • R. Ramesh

    University of California at Berkeley, University of California, Berkeley, CA, 94720, University of California-Berkeley, Department of Physics, and Material Science and Engineering, University of California, Berkeley, CA 94720, USA., Department of Physics, UC Berkeley, Dept. of Materials Science and Engineering, University of California, Berkeley, CA 94720

  • Feng Wang

    Department of Physics, UC Berkeley, University of California, Berkeley

  • Y.-H. Chu

    Department of Material Science and Engineering, National Chiao Tung University, HsinChu 30010, Taiwan., Department of Materials Science and Engineering, National Chiao Tung University

  • L. W. Martin

    Materials Science Division, LBNL

  • Nicola Spaldin

    UC Santa Barbara, Materials Department, UC Santa Barbara, University of California, Santa Barbara

  • A. Rother

    Institute of Structure Physics, Dresden University