Asymmetric magnetic domain wall motion under lateral and normal space inversion asymmetry with interfacial Dzyaloshinskii�Moriya interaction

Kayal, S and Maji, S and Mukhopadhyay, A and Anil Kumar, PS (2022) Asymmetric magnetic domain wall motion under lateral and normal space inversion asymmetry with interfacial Dzyaloshinskii�Moriya interaction. In: Journal of Magnetism and Magnetic Materials, 551 .

PDF jou_mag_mag_mat_2022.pdf - Published Version Restricted to Registered users only Download (2MB) | Request a copy

Abstract

The magnetic anisotropy of a typical magnetic sample with an easy axis perpendicular to the surface has many advantages over an in-plane easy axis due to advantages like better thermal stability, higher data storage density, lower energy consumption, etc. The perpendicular magnetic anisotropy arises due to the spatial inversion asymmetry (SIA) at the interfaces between a ferromagnet (FM) and a heavy metal (HM). In such systems, one can achieve a current-induced magnetization reversal (CIMR) via spin�orbit torque with the assistance of an in-plane (IP) magnetic field. This IP field requirement for the CIMR process is an obstacle for the practical application. Recent studies on CIMR at magnetic fields free condition are achieved by breaking the lateral structural symmetry by achieving thickness-gradient in a particular layer. In previous reports, the SIA normal to the surface in a heterostructure leads to an asymmetric contribution as chiral damping. In this work, a system Ta/Pt/CoFeB/Pt with normal and lateral SIA has been prepared by introducing a thickness-gradient in the FM CoFeB layer, which leads to create a tilted perpendicular magnetic anisotropy. The presence of the lateral SIA gives rise to another asymmetric component besides the chiral damping component. In this study, the total asymmetric component of the Ta/Pt/CoFeB/Pt heterostructure has been calculated into two contributions Ht and Hch, to extract the distinct information of the tilt asymmetry due to the lateral SIA and the chiral damping due to the normal SIA, respectively. In this study, by varying the bottom Pt thickness of the Ta/Pt/CoFeB/Pt heterostructures we have observed that the two asymmetry contributions Ht and Hch both decreased with increasing bottom Pt thickness. © 2022 Elsevier B.V.

Item Type:	Journal Article
Publication:	Journal of Magnetism and Magnetic Materials
Publisher:	Elsevier B.V.
Additional Information:	The copyright for this article belongs to Elsevier B.V.
Keywords:	Cobalt compounds; Digital storage; Domain walls; Energy utilization; Heavy metals; Iron compounds; Magnetic anisotropy; Magnetic domains; Magnetic fields; Magnetic storage; Magnetization reversal; Platinum, Asymmetric component; Current induced magnetization reversal; Domain wall motion; Dzyaloshinskii-Moriya interaction; Dzyaloshinskii�moriyum interaction; Easy axis; Inversion asymmetry; Magnetic domain walls; Perpendicular magnetic anisotropy; Thickness gradients, Damping
Department/Centre:	Division of Physical & Mathematical Sciences > Physics
Date Deposited:	16 Mar 2022 06:04
Last Modified:	16 Mar 2022 06:04
URI:	http://eprints.iisc.ac.in/id/eprint/71423

Actions (login required)

View Item