The fabrication of a skyrmion circuit which stabilizes skyrmions is important to realize micro- to nano-sized skyrmion devices. One example of promising skyrmion-based device is Brownian computers, which have been theoretically proposed, but not realized. It would require a skyrmion circuit in which the skyrmion is stabilized and easily movable. However, the usual skyrmion circuits fabricated by etching of the ferromagnetic film decrease the demagnetization field stabilizing the skyrmions, and thus prevent their formation. In this study, a skyrmion Brownian circuit implemented in a continuous ferromagnetic film with patterned SiO2 capping to stabilize the skyrmion formation. The patterned SiO2 capping controls the saturation field of the ferromagnetic layer and forms a wire-shaped skyrmion potential well, which stabilizes skyrmion formation in the circuit. Moreover, we implement a hub (Y-junction) circuit without pinning sites at the junction by patterned SiO2 capping. This technique enables the efficient control of skyrmion-based memory and logic devices, as well as Brownian computers.
@article{arxiv.1909.10130,
title = {Skyrmion Brownian circuit implemented in a continuous ferromagnetic thin film},
author = {Yuma Jibiki and Minori Goto and Eiiti Tamura and Jaehun Cho and Soma Miki and Hikaru Nomura and Titiksha Srivastava and Willy Lim and Stephane Auffret and Claire Baraduc and Helene Bea and Yoshishige Suzuki},
journal= {arXiv preprint arXiv:1909.10130},
year = {2020}
}