Phase separation in Pr$_{0.55}$Ca$_{1.45}$MnO$_{4}$ evidenced by magnetic excitations

ORAL

Abstract

At doping levels x$<$0.5, a coexistence of commensurate (CM) and incommensurate (ICM) magnetic peaks are observed in single-layered manganites Pr$_{1-x}$Ca$_{1+x}$MnO$_{4}$ with elastic neutron scattering. Temperature dependence measurements of the magnetic intensities with different energy resolutions indicate a glassy nature of the magnetic moments. The magnetic excitation measurements using inelastic neutron scattering on the x=0.45 system reveal both symmetric and asymmetric behaviors about the CM peak positions. This strongly suggests two types of magnetic excitations originated from separated phases: the CE-type magnetic phase and an additional electronic phase caused by extra electrons introduced into the CE template.

*The work was supported by NSF-DMR0453804 and DOE DE-FG02-05ER46202. ORNL is managed by UT-Battelle, LLC, for the U.S. Dept. of Energy under contract DE-AC05-00OR22725. This was also performed under the US-Japan Cooperative Program on Neutron Scattering.

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Authors

  • Songxue Chi

    • The University of Tennessee, Knoxville

  • Pengcheng Dai

    • University of Tennessee, Knoxville, TN 37996;Oak Ridge National Laboratory, Oak Ridge, TN 37831
    • University of Tennessee, Knoxville
    • Department of Physics, University of Tennessee, Oak Ridge National Lab

  • Feng Ye

    • Oak Ridge National Laboratory, Oak Ridge, TN 37831
    • Oak Ridge National Laboratory
    • ORNL

  • J. A. Fernandez-Baca

    • University of Tennessee, Knoxville, TN 37996;Oak Ridge National Laboratory, Oak Ridge, TN 37831
    • Oak Ridge National Laboratory

  • Hye Jung Kang

    • NIST Center for Neutron Scattering
    • Center for Neutron Research, National Institute of Standards and Technology,Gaithersburg, MD

  • J. W. Lynn

    • National Institute of Standards and Technology
    • NIST Center for Neutron Scattering
    • NIST
    • NCNR, National Institute of Standards and Technology, Gaithersburg, MD 20899
    • NCNR, National Institute of Standards and Technology

  • Y. Chen

    • National Institute of Standards and Technology
    • National Institute of Standards and Technology (NCNR), U. Maryland (Materials Science and Engineering)
    • NIST Center for Neutron Scattering
    • University of Maryland and NCNR

  • Yoshio Kaneko

    • University of Tokyo

  • Yoshinori Tokura

    • University of Tokyo