Effect of Confinement on Magnetism and Skyrmionic Properties of CoSi Nanoparticles

ORAL

Abstract

Quantum-confinement and surface effects often result in unusual magnetic ordering, modified ordering temperatures, and different spin structures in nanoparticles as compared to the corresponding bulk alloys [1, 2]. In sharp contrast to non-magnetic bulk equiatomic CoSi, we show a magnetic ordering at room temperature with a net magnetic moment m = 0.11 μB/Co for CoSi nanoparticles. The nanoparticles have an average size of 11.6 nm, and crystallize in the cubic B20 structure, which supports spin spirals and skyrmions with broken helicity caused by non-zero Dzyaloshinskii–Moriya (DM) interactions [3]. DC susceptibility and anomalous Hall resistivity measurements are used to discuss the effect of confinement within the small diameter of CoSi nanoparticles on the room-temperature skyrmionic properties, which are essential for exploiting these complex spin structures for practical applications.
References
[1] B. Das, B. Balasubramanian, D.J. Sellmyer et al. Nano Letters, 16, 1132 (2016).
[2] B. Balasubramanian, R. Skomski, D.J. Sellmyer et al. Nanoscale, 10, 13011 (2018).
[3] B. Balasubramanian, R. Pahari, R. Skomski, D. J. Sellmyer et al. submitted.

*This research is supported by the U.S. Department of Energy (DE-FG02-04ER46152 and DE-FG02-04ER4612), NSF-NNCI (1542182), and NCMN-NRI.

–

Presenters

  • Rabindra Pahari

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

Authors

  • Rabindra Pahari

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

  • Balamurugan Balasubramanian

    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska
    • Physics and Astronomy, University of Nebraska, Lincoln
    • Department of Physics and Astronomy, NCMN, University of Nebraska - Lincoln 68588-0299, USA

  • Ahsan Ullah

    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska
    • Department of Physics and Astronomy, NCMN, University of Nebraska - Lincoln 68588-0299, USA

  • Rohit Pathak

    • School of Basic Sciences, Indian Institute of Technology Mandi

  • Arti Kashyap

    • School of Basic Sciences, Indian Institute of Technology Mandi

  • Ralph Skomski

    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska
    • University of Nebraska
    • Physics and Astronomy, University of Nebraska, Lincoln
    • Department of Physics and Astronomy, NCMN, University of Nebraska - Lincoln 68588-0299, USA

  • George C Hadjipanayis

    • Univ of Delaware
    • Department of Physics and Astronomy, University of Delaware
    • Physics and Astronomy, University of Delaware

  • David Sellmyer

    • Department of Physics and Astronomy and Nebraska Center for Materials and Nanoscience, University of Nebraska
    • Physics and Astronomy, University of Nebraska, Lincoln
    • Department of Physics and Astronomy, NCMN, University of Nebraska - Lincoln 68588-0299, USA