Magnetotransport and magnetic textures in Ho/FeCoGd/β-W multilayers

Published

January 12, 2022

Author(s)

Ramesh Budhani, Vinay Sharma, Ezana Negusse, Jacob Casey, Arjun Pathak, Jerzy Sadowski, Brian Kirby

Abstract

The enhancement of interfacial Dzyaloshinskii – Moriya Interaction (DMI) in magnetic multilayers results in the stabilization of topological spin textures like chiral domain walls and skyrmions. Here we report on the evaluation of interface-driven magnetic interactions in a uniquely designed multilayer where each magnetic layer of two antiferromagnetically coupled sublattices of 3d and 4f moments is sandwiched between the layers of β-tungsten and holmium whose spin Hall angles are large but opposite in sign. The atomic and magnetic periodicity of these multilayers is established by polarized neutron reflectivity measurements and the presence of a stripe domain spin texture of zero remanence with x-ray photoelectron microscopy. Measurements of the Hall resistivity (ρ_xy(T, H)) together with static magnetization (M(T,H)) over a broad range of temperature (T) and magnetic field (H) indicate impending compensation between 3d and 4f sublattices at T > 350 K. These multilayers are characterized by a small (0.04 %) but positive magnetoresistance indicative of interface enhance scattering and a large (40 nΩ.m) and negative anomalous ρ_xy(T,H) which results from a parallel alignment of 4f moments with the external magnetic field. No distinct scaling is seen between ρ_xy(T,H), ρ_xx(T, H) and M(T,H) at temperatures above 200 K where the magnetization develops out-of-plane anisotropy. The field scans of ρ_xy at T > 200 K show a distinct cusp in the vicinity of magnetic saturation. These Hall data have been analyzed in the framework of a model where a distinct topological contribution to ρ_xy rides over the anomalous Hall resistivities of the 3d and 4f magnetic sublattices. It is argued that this topological effect draws its strength from the interfacial DMI and dominates ρ_xy(T,H) in the temperature regime where the 3d and 4f lattices are nearly compensated.

Citation

Physical Review B

Volume

105

Issue

2

Pub Type

Journals

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Keywords

Neutron

Citation

Budhani, R. , Sharma, V. , Negusse, E. , Casey, J. , Pathak, A. , Sadowski, J. and Kirby, B. (2022), Magnetotransport and magnetic textures in Ho/FeCoGd/β-W multilayers, Physical Review B, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=933624 (Accessed May 3, 2024)