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arXiv · 2012.10924

Creation of a Chiral Bobber Lattice in Helimagnet-Multilayer Heterostructures

Kejing Ran·Yizhou Liu·Yao Guang·David M. Burn·Gerrit van der Laan·Thorsten Hesjedal·Haifeng Du·Guoqiang Yu·Shilei Zhang
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Abstract

A chiral bobber is a localized three-dimensional magnetization configuration, terminated by a singularity. Chiral bobbers coexist with magnetic skyrmions in chiral magnets, lending themselves to new types of skyrmion-complementary bits of information. However, the on-demand creation of bobbers, as well as their direct observation remained elusive. Here, we introduce a new mechanism for creating a stable chiral bobber lattice state via the proximity of two skyrmion species with comparable size. This effect is experimentally demonstrated in a Cu$_2$OSeO$_3$/[Ta/CoFeB/MgO]$_4$ heterostructure in which an exotic bobber lattice state emerges in the phase diagram of Cu$_2$OSeO$_3$. To unambiguously reveal the existence of the chiral bobber lattice state, we have developed a novel characterization technique, magnetic truncation rod analysis, which is based on resonant elastic x-ray scattering.

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Kejing Ran, Yizhou Liu, Yao Guang, David M. Burn, Gerrit van der Laan, Thorsten Hesjedal, Haifeng Du, Guoqiang Yu, Shilei Zhang. 2020-12-20. Creation of a Chiral Bobber Lattice in Helimagnet-Multilayer Heterostructures. https://doi.org/10.1103/physrevlett.126.017204

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