Magnetic Neutron Scattering Study of Rare-Earth Titanates

ORAL

Abstract

The Mott-insulating rare-earth (R) titanates (RTiO3) are known to host ferromagnetic-antiferromagnetic transitions in solid-solution systems such as Y1-xLaxTiO3, as well as metal-insulator transitions in charge carrier-doped systems such as Y1-xCaxTiO3. Neutron scattering studies have been largely restricted to the undoped YTiO3 and LaTiO3. Here, we report on our neutron scattering work on the magnetic order and excitations in the doped systems Y1-xLaxTiO3 and Y1-xCaxTiO3, using triple-axis spectrometry and small-angle neutron scattering (SANS). We find a strong reduction in the transition temperature and ordered magnetic moment, but accompanied by very little change in the spin-wave dispersion in the Y1-xLaxTiO3 system as we approach the critical doping x~0.3. SANS results suggest a rotation of the easy axis with substitution, development of magnetic inhomogeneities on ~10 nm scales, and distinct changes in critical scattering as the magnetic crossover is approached. These results suggest significant changes in the magnetic ground state as one approaches the crossover. Initial studies on the Y1-xCaxTiO3 system will also be reported.

*Work supported by the Department of Energy through the University of Minnesota Center for Quantum Materials under DE-SC0016371.

–

Presenters

  • Sajna Hameed

    • University of Minnesota
    • School of Physics and Astronomy, University of Minnesota

Authors

  • Sajna Hameed

    • University of Minnesota
    • School of Physics and Astronomy, University of Minnesota

  • Sami El-Khatib

    • Chemical Engineering and Materials Science, University of Minnesota

  • Joseph Joe

    • School of Physics and Astronomy, University of Minnesota

  • Karl Olson

    • Chemical Engineering and Materials Science, University of Minnesota

  • Masaaki Matsuda

    • Neutron Sciences Directorate, Oak Ridge National Laboratory
    • Oak Ridge National Laboratory
    • Neutron Science Directorate, Oak Ridge National Laboratory
    • Oak Ridge National Lab

  • Songxue Chi

    • Oak Ridge National Laboratory
    • Quantum Condensed Matter Division, Oak Ridge National Laboratory, TN 37831
    • Neutron Scattering Division, Oak Ridge National Laboratory
    • Oak Ridge National Lab

  • Tao Hong

    • Oak Ridge National Laboratory
    • Neutron Scattering Division, Oak Ridge National Laboratory
    • Neutron Scattering Division, Oak-Ridge National Laboratory
    • Neutron Scattering Division, Oak Ridge National Lab

  • Daniel Pajerowski

    • Oak Ridge National Laboratory
    • Oak Ridge National Lab

  • Travis J Williams

    • Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, TN 37831, USA
    • Oak Ridge National Laboratory

  • John Barker

    • NIST Center for Neutron Research

  • Chris Leighton

    • Chemical Engineering and Materials Science, University of Minnesota
    • Univ of Minn - Minneapolis
    • University of Minnesota

  • Martin Greven

    • University of Minnesota
    • School of Physics and Astronomy, University of Minnesota
    • Physics and Astronomy, University of Minnesota