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arXiv · 2007.06008

Energy-efficient generation of skyrmion phases in Co/Ni/Pt-based multilayers using Joule heating

Jeffrey A. Brock·Sergio A. Montoya·Mi-Young Im·Eric E. Fullerton
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Abstract

We have studied the effects of electrical current pulses on skyrmion formation in a series of Co/Ni/Pt-based multilayers. Transmission X-ray microscopy reveals that by applying electrical current pulses of duration and current density on the order of $\tau$=50 $\mu$s and j=1.7x10$^1$$^0$ A/m$^2$, respectively, in an applied magnetic field of $\mu$$_0$Hz=50 mT, stripe-to-skyrmion transformations are attained. The skyrmions remain stable across a wide range of magnetic fields, including zero field. The skyrmions then remain stable across a wide range of magnetic fields, including zero field. We primarily attribute the transformation to current-induced Joule heating on the order of ~125 K. Reducing the magnetic moment and perpendicular anisotropy using thin rare-earth spacers dramatically reduces the pulse duration, current density, and magnetic field necessary to 25 $\mu$s, 2.4x10$^9$ A/m$^2$, and 27 mT, respectively. These findings show that energetic inputs allow for the formation of skyrmion phases in a broad class of materials and that material properties can be tuned to yield more energy-efficient access to skyrmion phases.

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Jeffrey A. Brock, Sergio A. Montoya, Mi-Young Im, Eric E. Fullerton. 2020-07-12. Energy-efficient generation of skyrmion phases in Co/Ni/Pt-based multilayers using Joule heating. https://doi.org/10.1103/physrevmaterials.4.104409

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