Simultaneous breaking of lattice symmetry and spin frustration in triangular lattice antiferromagnet $\rm CuFeO_2$

ORAL

Abstract

We use high resolution synchrotron X-ray and neutron diffraction to study the geometrically frustrated triangular lattice antiferromagnet (TLA) $\rm CuFeO_2$. We show that the occurrence of the two magnetic transitions, at $14$~K and $11$~K, respectively is accompanied simultaneously by a second-and first- order structural phase transitions from a hexagonal structure to a monoclinic form. This is the first observation of two successive spin-driven structural transitions directly coupled with incommensurate and commensurate magnetic orderings in frustrated TLA systems. \newline \newline This work is supported by the U. S. NSF DMR-0453804 and DOE Nos. DE-FG02-05ER46202 and DE-AC05-00OR22725 with UT/Battelle LLC. Use of the Advanced Photon Source was supported by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. W-31-109-Eng-38.

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Authors

  • Y. Ren

    • XFD/XOR, Argonne National Laboratory

  • Feng Ye

    • Oak Ridge National Laboratory
    • Center for Neutron Scattering, Oak Ridge National Laboratory

  • Q. Huang

    • NIST Center for Neutron Research, NIST

  • J.A. Fernandez-Baca

    • Center for Neutron Scattering, Oak Ridge National Laboratory \& Dept of Physics and Astronomy, Univ. of Tennessee

  • Pengcheng Dai

    • Dept of Physics and Astronomy, Univ. of Tennessee \& Center for Neutron Scattering, Oak Ridge National Laboratory

  • J.W. Lynn

    • NIST Center for Neutron Research, NIST

  • T. Kimura

    • Los Alamos National Laboratory