Tuning isolated zero-field skyrmions and spin spirals at room-temperature in synthetic ferrimagnetic multilayers

Author(s)

Brandao, J. ; Dugato, D. A. ; dos Santos, M. V. Puydinger ; Beron, Fanny ; Cezar, J. C.

• Document type: Journal article
• Source: Applied Surface Science; v. 585, p. 7-pg., 2022-05-30.

Abstract

We demonstrate the observation of spin spirals and individual skyrmions in synthetic Pt/CoGd/Pt ferrimagnetic multilayers at room-temperature without the assistance of an external magnetic field. The magnetic coupling between the magnetic moments of Co and Gd, was investigated across various CoGd thicknesses by element specific X-ray magnetic circular dichroism (XMCD) performed around the Co L-2,L-3 and Gd M(4,5 )edges. It show s an uncompensated ferrimagnetic orientation between the Co and Gd atoms preserved at ambient conditions, even for sub-nanometer thick layers. In addition, with the tunable enhanced perpendicular magnetic anisotropy K-u and remnant magnetization M-R found for thinner CoGd & LE; (0.9 nm) isolated zero-field skyrmions were imaged by magnetic force microscopy (MFM) as the magnetic ground state, replacing the spin spirals observed for thicker CoGd layers & GE; (1.2 nm). Such stable skyrmions in perpendicularly magnetized materials with antiparallel exchange-coupling are potential candidates for energy-efficient data storage and processing in future antiferromagnetic-based devices. (AU)

• FAPESP's process: 20/07397-7 - Control and imaging of interfacial patterned skyrmionic textures in perpendicular magnetic anisotropy multilayer systems
• Grantee: Fanny Béron
• Support Opportunities: Regular Research Grants
• FAPESP's process: 17/10581-1 - Emergent phenomena in reduced dimension systems
• Grantee: Pascoal Jose Giglio Pagliuso
• Support Opportunities: Special Projects
• FAPESP's process: 12/51198-2 - Growth and characterization of the electronic structure of oxides multiferroics heterostructures
• Grantee: Júlio Criginski Cezar
• Support Opportunities: Research Grants - Young Investigators Grants