Observation of Néel Skyrmions in an Exchange Coupled Cobalt/Palladium Based Multi-layers of Metallic Compounds at High Temperatures

B.U.V. Prashanth; Mohammed Riyaz Ahmed

doi:10.6180/jase.202104_24(2).0005

Observation of Néel Skyrmions in an Exchange Coupled Cobalt/Palladium Based Multi-layers of Metallic Compounds at High Temperatures

Computer Science and Information Engineering

B.U.V. Prashanth This email address is being protected from spambots. You need JavaScript enabled to view it.¹ and Mohammed Riyaz Ahmed²

¹School of Electronics and Communication Engineering, REVA University, Bengaluru, India
²School of Multidisciplinary Studies, REVA University, Bengaluru, India

Received: July 19, 2020
Accepted: October 5, 2020
Publication Date: April 1, 2021

Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

Download Citation: ||https://doi.org/10.6180/jase.202104_24(2).0005

ABSTRACT

In the class of cubic B20 transition metal silicides and germanides, the skyrmions and skyrmion lattices have so far been studied most extensively. Certain groups of materials in which skyrmions were identified include the Perovskites and Heusler systems. In this paper, the skyrmions chiral Néel characterization is illustrated via Lorentz transmission electron microscopy. Further utilizing magnetic-imaging and Hall-transport in a functionally viable multilayer sample, the topological-hall resistivity rises over a wide range of temperature and magnetic field with the isolated-skyrmion density is observed, verifying the effect of the skyrmion geometric-phase on electron transport. The observed bulk Néel skyrmions in an exchange coupled cobalt/palladium(Co/Pd) based multi-layers of metallic compounds at high temperatures up to a maximum of 220 K followed by a larger region characterized by spin from in-to out-of-plane. In fact, the skyrmions are extremely resilient to in-plane magnetic fields and can be stable in a zero magnetic field using appropriate cooling methods in field over a very wide ambient temperature of up to 5.5 K. At low temperatures (of < 13 K) the Néel skyrmions have been observed recently in distinct non-metallic compounds, in bulk crystals with broken inversion symmetry with a non-adiabatic footprint, multiband transport, interfacial interactions.

Keywords: Spintronics, Lorentz transmission electron microscopy, Magnetic Skyrmions, non-centrosymmetric, Dzyaloshinskii–Moriya interaction

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