Operando control of skyrmion density in a Lorentz transmission electron microscope with current pulses

Abstract

Magnetic skyrmions hold promise for spintronic devices. To explore the dynamical properties of skyrmions in devices, a nanoscale method to image spin textures in response to a stimulus is essential. Here, we apply a technique for operando electrical current pulsing of chiral magnetic devices in a Lorentz transmission electron microscope. In ferromagnetic multilayers with interfacial Dzyaloshinskii–Moriya interaction, we study the creation and annihilation of skyrmions localized by point-like pinning sites due to defects. Using a combination of experimental and micromagnetic techniques, we establish a thermal contribution for the creation and annihilation of skyrmions in our study. Our work reveals a mechanism for controlling skyrmion density, which enables an examination of skyrmion magnetic field stability as a function of density. We find that high-density skyrmion states are more stable than low-density states or isolated skyrmions resisting annihilation over a magnetic field range that increases monotonically with density.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 21, 2020
Source ID
10.1063/5.0020373

Entities

People

  • Albert M. Park
  • David A. Muller
  • Gregory D Fuchs
  • Lijun Zhu
  • Xiyue S. Zhang
  • Zhen Chen

Organizations

  • Cornell University
  • Defense Advanced Research Projects Agency
  • National Science Foundation
  • Office of Naval Research Global

Tags

Fields of Study

  • Physics

Readers

  • Materials Science and Engineering.
  • Plasma Physics.
  • Quantum Dot Semiconductor Device Photonics and Graphene Optoelectronic Materials and THz Physics.

Technology Areas

  • Microelectronics