Investigation of Intrinsic Physical Properties for High Quality FeSi Single Crystals

ORAL

Abstract

We report physical properties of single-crystalline FeSi over a wide temperature range from 1.8 K to 400 K. The FeSi crystals were evaluated by means of X-ray diffraction, specific heat, and magnetization measurements and found to have a very low concentration of magnetic impurities ~100 ppm. In the temperature range 150-67 K, the electrical transport behavior is consistent with activated behavior with an energy gap of 57 meV, below which the resistivity is significantly smaller together with a sign change of the Hall coefficient and magneto-resistivity. Further decrease of the temperature results in a sharp reversible transition from a negative slope to a positive slope of ρ(T) at 19 K. Corresponding magnetization and magneto-resistivity measurements suggest that there is no magnetic order associated with this transition. Furthermore, no feature can be observed in specific heat measurements. The results suggest complicated electron transport properties and provide evidence of a conducting surface state in FeSi at low temperatures.

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Presenters

  • Yuankan Fang

    Univ of California - San Diego, Materials Science and Engineering Program, Univ of California - San Diego

Authors

  • Yuankan Fang

    Univ of California - San Diego, Materials Science and Engineering Program, Univ of California - San Diego

  • Sheng Ran

    Department of Physics, University of California, San Diego, Univ of California - San Diego, Physics, University of California, San Diego, Department of Physics, Univeristy of Maryland, Department of Physics, University of Maryland

  • 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

  • Weiwei Xie

    Department of Chemistry, Louisiana State University, Louisiana State Univ - Baton Rouge, Louisiana State Univ, Department of Chemistry, Louisiana state University, Chemistry, Lousiana State University, Department of Physics and Astronomy, Louisiana State Univ - Baton Rouge