Structural Stabilization of Antiferromagnetism at the Surface of a Layered Manganite

ORAL

Abstract

Here, we present evidence to support the idea that the distinct surface electronic and magnetic state seen in the double-layered manganites (La$_{2}-_{2x}$Sr$_{1+2x}$Mn$_{2}$O$_{7}$, with dopings of 0.3 $< \quad x \quad <$ 0.4) is driven solely by a subtle change in the lattice at the surface, which is consistent with the strong coupling between the lattice, charge, and spin degrees of freedom in these doped transition-metal oxides. A combined experimental and theoretical approach was essential in understanding the origin of the nonmagnetic surface phase. The new measurements and calculations give an insightful explanation of the previous x-ray and tunneling data, which indicated a nonmagnetic and insulating surface bilayer.

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Authors

  • E. Ward Plummer

    • Louisiana State University, Baton Rouge, LA
    • Dept. of Physics \& Astronomy, LSU

  • V.B. Nascimento

    • Louisiana State University, Baton Rouge, LA

  • R.G. Moore

    • Stanford University, Stanford, CA

  • H. Liu

    • The University of Tennessee, Knoxville, TN

  • M.H. Pan

    • Oak Ridge National Laboratory, Oak Ridge, TN

  • D. Mazur

    • Argonne National Laboratory, Argonne, IL

  • J.W. Freeland

    • Argonne National Laboratory, Argonne, IL

  • K.E. Gray

    • Argonne National Laboratory, Argonne, IL

  • R.A. Rosenberg

    • Argonne National Laboratory, Argonne, IL

  • H. Zheng

    • Argonne National Laboratory, Argonne, IL

  • J.F. Mitchell

    • Argonne National Laboratory, Argonne, IL

  • R. Saniz

    • Northwestern University, Evanston, IL

  • A.J. Freeman

    • Northwestern University, Evanston, IL

  • J. Rundgren

    • Royal Institute of Technology, Sweden