Magnetic and Electron-Transport Properties of Co<sub>2</sub>Si Nanomagnets

ORAL

Abstract

Magnetic and spin-transport properties of nanostructured materials have attracted much attention in the context of spintronic devices [1, 2]. In this work, we investigate ferromagnetism and magnetotransport in thin films of Co2Si nanoclusters experimentally and theoretically. The nanoclusters form an orthorhombic structure (space group: Pnma) and have an average size d ≈ 11.3 nm with a standard deviation of σ/d ≈ 0.19. The nanoclusters exhibit room-temperature ferromagnetism with a substantial saturation magnetization of 0.70 μB/Co at 10 K and 0.49 μB/Co at 300K. On decreasing temperature from 300 K, the nanoclusters show electron-transport properties unusual for a ferromagnetic metal, including an increase of Hall resistivity and a non-monotonic change of negative magnetoresistance with a peak at around 100 K. The underlying physics is explained on the basis of the large polarization of surface spins and variation in the degree of their misalignments due to temperature-dependent effective anisotropy [3].
[1] N. Nagaosa et al., Rev. Mod. Phys. 82, 1539 (2010).
[2] B. Balamurugan et al., Appl. Phys. Lett. 106, 242401 (2015)
[3] B. Balamurugan et al. (Submitted)

*This research is primarily supported by the U.S. Department of Energy under the award number DE-FG02-04ER46152.

Presenters

  • Rabindra Pahari

    • Nebraska Center for Materials and Nanoscience and Department of Physics and Astronomy, University of Nebraska - Lincoln
    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska - Lincoln
    • University of Nebraska - Lincoln
    • Department of Physics and Astronomy, University of Nebraska-Lincoln

Authors

  • Rabindra Pahari

    • Nebraska Center for Materials and Nanoscience and Department of Physics and Astronomy, University of Nebraska - Lincoln
    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska - Lincoln
    • University of Nebraska - Lincoln
    • Department of Physics and Astronomy, University of Nebraska-Lincoln
  • Balamurugan Balasubramanian

    • Nebraska Center for Materials and Nanoscience and Department of Physics and Astronomy, University of Nebraska - Lincoln
    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska - Lincoln
    • University of Nebraska - Lincoln
    • Department of Physics and Astronomy, University of Nebraska-Lincoln
  • Tom A. George

    • Department of Physics and Astronomy, University of Nebraska-Lincoln
  • Priyanka Manchanda

    • Howard University
    • Department of Physics and Astronomy, Howard University
  • Ahsan Ullah

    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska - Lincoln
    • University of Nebraska - Lincoln
    • Department of Physics and Astronomy, University of Nebraska-Lincoln
  • Ralph Skomski

    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska - Lincoln
    • University of Nebraska - Lincoln
    • Department of Physics and Astronomy, University of Nebraska-Lincoln
  • David J Sellmyer

    • Nebraska Center for Materials and Nanoscience and Department of Physics and Astronomy, University of Nebraska - Lincoln
    • University of Nebraska-Lincoln
    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska - Lincoln
    • University of Nebraska - Lincoln
    • Department of Physics and Astronomy, University of Nebraska-Lincoln