Work

Stabilized biskyrmion states in annealed CoFeB bilayer with different interfaces

Year: 2025

Type: article

Abstract: This study investigates the stability of skyrmions and biskyrmions in perpendicular magnetic tunneling junctions with a thick CoFeB/Ta/CoFeB free layer. The samples showed a magnetoresistance of ∼ 41 % when annealed at 230 °C. Magnetic force microscopy revealed the existence of skyrmions and biskyrmions at room temperature in the as-deposited state and under an external magnetic field. Annealing at 330 °C enhanced interfacial Dzyaloshinskii-Moriya interaction (DMI) and crystallinity, enabling the spontaneous coexistence of these topological structures. Micromagnetic simulations explored the interplay between DMI strength, sign, and skyrmion chirality. Skyrmions exhibited repulsive interactions while biskyrmions displayed attractive interactions due to the difference in helicities. The study highlights the influence of multilayer structure and varying Ta layer thicknesses on the DMI chirality, which modulates the formation of complex spin textures. These results provide an understanding of skyrmion and biskyrmion dynamics and their potential for spintronic applications, including racetrack memory and data storage technologies.

Source: Materials Today Electronics

DOI: 10.1016/j.mtelec.2025.100166

Authors: Warda Al Saidi, Selma Amara, Myo T. Zar Myint, Salim Al Harthi, Gianluca Setti, Rachid Sbiaa

Institutions: Sultan Qaboos University, King Abdullah University of Science and Technology

Language: English

Topic: Magnetic properties of thin films

Subfield: Atomic and Molecular Physics, and Optics

Field: Physics and Astronomy

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $2,860

Funder: Sultan Qaboos University