Effect of Annealing on Maze Domains in Topological Insulator - Magnetic Multilayer Heterostructures

Benjamin A. Brereton; Soumyarup Hait; Christy J. Kinane; Francesco Maccherozzi; Ahmet Yagmur; Satoshi Sasaki; Thomas A. Moore; Sean Langridge; Christopher H. Marrows

arXiv · 2610.29694

Effect of Annealing on Maze Domains in Topological Insulator - Magnetic Multilayer Heterostructures

Benjamin A. Brereton·Soumyarup Hait·Christy J. Kinane·Francesco Maccherozzi·Ahmet Yagmur·Satoshi Sasaki·Thomas A. Moore·Sean Langridge·Christopher H. Marrows

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Abstract

Combining topological insulators with chiral magnetic multilayers offers the opportunity to greatly enhance the spin-orbit torque (SOT) driven manipulation of hosted spin textures, however this also exposes devices to the often poor temperature stability of the commonly used, Bi$_2$X$_3$-based (X is a chalcogenic element), topological insulator films. In this work we demonstrate through in-situ-annealing and polarised neutron reflectometry that the multilayer at a Bi$_2$Se$_3$ interface remains magnetically robust up to a temperature of 350 $^{\circ}$C: even as the Bi$_2$Se$_3$ epilayer structurally deteriorates. Through x-ray photoemission electron microscopy, an intermediate annealing temperature of $\sim$ 200 $^{\circ}$C was found to improve the domain ordering of the multilayer, allowing for field-induced skyrmion nucleation, all whilst sustaining minimal damage to the topological insulator

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Benjamin A. Brereton, Soumyarup Hait, Christy J. Kinane, Francesco Maccherozzi, Ahmet Yagmur, Satoshi Sasaki, Thomas A. Moore, Sean Langridge, Christopher H. Marrows. 2026-10-21. Effect of Annealing on Maze Domains in Topological Insulator - Magnetic Multilayer Heterostructures. https://arxiv.org/abs/2610.29694

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