Maximization of surface-enhanced transversal magneto-optic Kerr effect in Au/Co/Au thin films

TL;DR

This paper presents a method to optimize the thickness of Au/Co/Au thin films to maximize the transversal magneto-optic Kerr effect, achieving nearly ninefold enhancement using plasmonic properties.

Contribution

The authors develop a theoretical and experimental approach to optimize Au/Co/Au structures for enhanced T-MOKE, balancing plasmonic and magneto-optic properties.

Findings

Achieved nearly ninefold increase in MO signal at 532nm

Validated theoretical predictions with experimental results

Identified optimal thicknesses balancing plasmonic and MO effects

Abstract

In order to maximize the transversal magneto-optic Kerr effect (T-MOKE) of a Au/Co/Au structure, we propose a method to obtain the optimum thickness values. A criteria based on preserving good plasmonic properties has been included as part of this method. Using the theoretical prediction, we grew Au/Co/Au trilayers and perform optical andMO characterization using the Kretschmann configuration. The results admit very easy interpretation in terms of the interaction between the magneto-optical and plasmonic properties dictating the optimal thicknesses of the structure. Moreover, we have grown and characterized the optimized structure finding good agreement with theory reaching, for a 532nm green laser, amaximal surface magneto-optic (MO) signal enhancement of close to nine folds with respect to the signal without plasmonic excitation.