Electronic excitations in a one-dimensional J=$\frac{1}{2}$ antiferromagnet observed by Raman scattering

POSTER

Abstract

A major focus of experimental interest in low-dimensional iridium oxides has been to explore the interplay of quantum fluctuation, spin-orbit coupling and electron correlation effects. Ba$_5$CuIr$_3$O$_{12}$ serves as an ideal playground and contains weakly-interacting chains along which J=$\frac{1}{2}$ iridium ions are antiferromagnetically coupled. The intercept obtained by extrapolating high-temperature inverse static magnetic susceptibility is around -270\,K but no magnetic ordering occurs down to 4\,K\footnote{G. R. Blake et al., Chem. Mater. 10, 3536 (1998)}, indicating quanum fluctuation induced magnetic frustration. Here, we report polarized inelastic light-scattering spectrum of Ba$_5$CuIr$_3$O$_{12}$ as function of exciting laser energy and temperature. Low-energy magnetic response below 100\,meV only appears when the system is excited along the chain direction, corresponding to local antiferromagnetic correlations. On the other hand, the spectral lineshape of high-energy d-d electronic transitions at 570\,meV sheds light on the competition between localizing and itinerant tendency of electrons on iridium extended 5d orbits.

Authors

  • Mai Ye

    Department of Physics and Astronomy, Rutgers University

  • Jae-Wook Kim

    Department of Physics and Astronomy, Rutgers University

  • Debbie Andres

    Department of Applied Physics and Department of Physics, Columbia University, Istituto Italiano di Tecnologia, Graphene Labs, Italy, Department of Physics and Astronomy, Purdue University, Department of Electrical Engineering, Princeton University, Department of Applied Physics and Applied Mathematics, Columbia University, NJIT, New Jersey Inst of Technology, New Jersey Inst of Tech, New Jersey Institute of Technology, Center for Advanced Radiation Sources, University of Chicago, High Pressure Science and Technology Advanced Research, State University of New York at Stony Brook, Rutgers University, NIST, Brookhaven National Laboratory, University of Chicago, University of South Florida, ETH Zurich, Max Planck POSTECH/Korea Research Initiative, University of Virginia, Rutgers University - Camden, New Jersey Institute of technology, Shaanxi Normal University, Pohang Science and Technology University, Sungkyunkwan University, Northern Illinois University and Argonne National Laboratory, Beijing National Laboratory for Condensed Matter Physics , and Institute of Physics, Chinese Academy of Sciences, Rutgers U., Orsova Engineers, U.S. Naval Research Laboratory, Center for Space Science and Engineering Research, Virginia Tech, Virginia., Princeton University, NASA Goddard Space Flight Center, Villanova University, SOFIA/USRA, Jet Propulsion Laboratory, Hudson Regional Health Commision, Rutgers University, College of William & Mary, Department of Physics, Drexel University, Drexel University, Drexel Universty, University of Massachusetts Amherst, Pohang Institue of Science and Technology, Indiana University - Purdue University Indianapolis, Department of Physics, University of Maryland, Naval Research Laboratory, Towson Univ, Rice University, Independence Blue Cross Cardiovascular Research Center, Lewis Katz School of Medicine, Temple University, Philadelphia, PA, Department of Physics, Temple University, PulseTorr LLC, Department of Chemistry, West Chester University, Department of Physics, West Chester University, College of William and Mary Dept. of Physics, University of Virginia Dept. of Materials Science and Engineering, United States Naval Academy, Rutgers The State University of New Jersey, Univ of Maryland-College Park, Los Alamos National Laboratory, POSTECH, New Jersey Institute of Technology, Department of Electrical and Computer Engineering, HamSCI/ARRL, Virginia Tech, Rutgers University-Camden, University of Washington, Rutgers, The State University of New Jersey

  • Sang-Wook Cheong

    Department of Physics and Astronomy, Rutgers University, Rutgers University, New Brunswick, Rutgers University, Rutgers Univ, Rutgers Center for Emergent Materials and Department of Physics and Astronomy, Rutgers University

  • Girsh Blumberg

    Rutgers University, Department of Physics and Astronomy, Rutgers University