Properties of the Predicted Multiferroic Ca$_{3}$Mn$_{2}$O$_{7}$ - Experiment

ORAL

Abstract

We have studied the properties of epitaxial films of Ca$_{3}$Mn$_{2}$O$_{7}$, an $n=2$ Ruddlesden-Popper phase. This material has been predicted to have novel multiferroic properties, including electric field switching of the magnetization [1]. 50 nm thick unstrained Ca$_{3}$Mn$_{2}$O$_{7}$ films were grown by reactive MBE on (110) YAlO$_{3}$ single crystal substrates. XRD shows that the Ca$_{3}$Mn$_{2}$O$_{7}$ films are single phase and epitaxial with (001) Ca$_{3}$Mn$_{2}$O$_{7}$ // (110) YAlO$_{3}$. Our films show a transition to a weakly ferromagnetic or canted antiferromagnetic state below 120K. The magnetic properties have strong anisotropy with a clear transition visible with an in-plane applied field, but none along the out of plane direction. Second harmonic generation results show that a weak polar order exists at room temperature and it persists until $\sim $700$^{\circ}$C. We also report on the low temperature dielectric properties of the material. \\[4pt] [1] N. A. Benedek and C. J. Fennie, arXiv:1007.1003v1.

–

Authors

  • R. Misra

    • The Pennsylvania State University, University Park, PA

  • Carolina Adamo

    • Cornell University, NY
    • Cornell University

  • Nicole Benedek

    • Cornell University, NY
    • School of Applied and Engineering Physics, Cornell University
    • Cornell University

  • Sava Denev

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

  • A. SenGupta

    • The Pennsylvania State University, University Park, PA

  • J.A. Mundy

    • Cornell University, NY

  • J.H. Lee

    • The Pennsylvania State University, University Park, PA

  • D.A. Muller

    • Cornell University, NY

  • Venkatraman Gopalan

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

  • Craig Fennie

    • Cornell University
    • Cornell University, NY
    • School of Applied and Engineering Physics, Cornell University
    • School of Applied and Engineering Physics, Cornell University, Ithaca, NY

  • Darrell Schlom

    • Cornell University
    • Cornell University, NY

  • Peter Schiffer

    • The Pennsylvania State University, University Park, PA
    • Pennsylvania State University
    • Department of Physics and Materials Research Institute, The Pennsylvania State University, University Park, Pennsylvania 16802, USA
    • Department of Physics and Materials Research Institute, Pennsylvania State University, University Park, PA 16802
    • Penn State University