Effect of Cr spacer on structural and magnetic properties of Fe/Gd multilayers

TL;DR

This study investigates how a thin chromium spacer influences the structural and magnetic properties of Fe/Gd multilayers, revealing modifications in magnetic coupling and layer characteristics through experimental and theoretical analysis.

Contribution

It provides new insights into the effects of Cr spacers on Fe/Gd superlattices, combining experimental data with mean-field model simulations.

Findings

Cr spacers reduce antiferromagnetic coupling between Fe and Gd

Introduction of Cr modifies structural and magnetic properties of layers

Temperature-dependent effective field parameter improves data agreement

Abstract

In this work we analyse the role of a thin Cr spacer between Fe and Gd layers on structure and magnetic properties of a [Fe(35A)/Cr(tCr)/Gd(50A)/Cr(tCr)]x12 superlattice. Samples without the Cr spacer (tCr=0) and with a thin tCr=4A are investigated using X-ray diffraction, polarized neutron and resonance X-ray magnetic reflectometry, SQUID magnetometery, magneto-optical Kerr effect and ferromagnetic resonance techniques. Magnetic properties are studied experimentally in a wide temperature range 4-300K and analysed theoretically using numerical simulation on the basis of the mean-field model. We show that a reasonable agreement with the experimental data can be obtained considering temperature dependence of the effective field parameter in gadolinium layers. The analysis of the experimental data shows that besides a strong reduction of the antiferromagnetic coupling between Fe and Gd, the introduction of Cr spacers into Fe/Gd superlattice leads to modification of both structural and magnetic characteristics of the ferromagnetic layers.