Structural studies of URu<sub>2</sub>Si<sub>2</sub> near the hidden order transition using X-ray crystallography

ORAL

Abstract

URu2Si2 is known for its hidden order transition at T=17.5K whose physical origin is still not agreed. We present an x-ray crystallographic study of the structure of URu2Si2 over the temperature range 23 K < T < 5.5 K. Using a large, image plate detector, we recorded 32 reflections and performed a full structure refinement at each temperature. We found that, as the temperature is lowered, the spacegroup of the crystal does not change, but the Si atoms translate along the b axis by 0.78Å (0.19 b) in response to the hidden order transition. Our study suggests that the order parameter associated with this transition is weakly coupled to a Si phonon of Eu symmetry.

*This work was supported by DOE Office of Basic Energy Sciences grant no. DE-FG02-06ER46285.

–

Presenters

  • Xiaolan Sun

    • Univ of Illinois - Urbana

Authors

  • Xiaolan Sun

    • Univ of Illinois - Urbana

  • John Mydosh

    • Leiden Univ

  • M Brian Maple

    • Department of Physics, University of California, San Diego
    • University of California, San Diego
    • Physics, University of California, San Diego
    • Univ of California - San Diego
    • Department of Physics and Center for Advanced Nanoscience, University of California, San Diego
    • Department of Physics, Center for Advanced Nanoscience,Materials Science and Engineering Program , Univ of California - San Diego
    • Department of Physics, University of California San Diego
    • Physics, Univ of California - San Diego
    • University of California-San Diego
    • UC San Diego
    • Physics, UC San Diego

  • Hsiang-Hsi Kung

    • Quantum Matter Institute, Univ of British Columbia
    • University of British Colombia
    • Institute of Physics , Academia Sinica

  • Sangjun Lee

    • Physics/MRL, Univ of Illinois - Urbana
    • Univ of Illinois - Urbana
    • Department of Physics, University of Illinois

  • Gilberto De La Pena

    • Physics/MRL, Univ of Illinois - Urbana
    • Univ of Illinois - Urbana
    • Department of Physics, University of Illinois

  • Girsh Blumberg

    • Physics and Astronomy, Rutgers Univiversity
    • Rutgers Univ

  • Peter Abbamonte

    • University of Illinois
    • Univ of Illinois - Urbana
    • Physics/MRL, Univ of Illinois - Urbana
    • Department of Physics, University of Illinois
    • Department of Physics and Materials Research Laboratory, University of Illinois