Magnetic skyrmions are localized chiral spin textures, which offer great promise to store and process information at the nanoscale. In the presence of asymmetric exchange interactions, their chirality, which governs their dynamics, is generally considered as an intrinsic parameter set during the sample deposition. In this work, we experimentally demonstrate that a gate voltage can control this key parameter. We probe the chirality of skyrmions and chiral domain walls by observing the direction of their current-induced motion and show that a gate voltage can reverse it. This local and dynamical reversal of the chirality is due to a sign inversion of the interfacial Dzyaloshinskii-Moriya interaction that we attribute to ionic migration of oxygen under gate voltage. Micromagnetic simulations show that the chirality reversal is a continuous transformation, in which the skyrmion is conserved. This control of chirality with 2 - 3 V gate voltage can be used for skyrmion-based logic devices, yielding new functionalities.
@article{arxiv.2204.04031,
title = {Gate-controlled skyrmion and domain wall chirality},
author = {Charles-Elie Fillion and Johanna Fischer and Raj Kumar and Aymen Fassatoui and Stefania Pizzini and Laurent Ranno and Djoudi Ourdani and Mohamed Belmeguenai and Yves Roussigné and Salim-Mourad Chérif and Stéphane Auffret and Isabelle Joumard and Olivier Boulle and Gilles Gaudin and Liliana Buda-Prejbeanu and Claire Baraduc and Hélène Béa},
journal= {arXiv preprint arXiv:2204.04031},
year = {2022}
}