Chapter 16
Antiferromagnetic Skyrmions
and Bimerons
Laichuan Shen, Xue Liang, Jing Xia, Xichao Zhang, Motohiko Ezawa,
Oleg A. Tretiakov, and Yan Zhou
Abstract The topological spin textures, such as magnetic skyrmions and bimerons,
are currently a hot topic in condensed matter physics. Magnetic skyrmions are
swirling spin textures, which can be stabilized in chiral magnets with perpendicular magnetic anisotropy, while magnetic bimerons can be regarded as the counterpart of skyrmions in magnetic systems with in-plane anisotropy. Both magnetic
skyrmions and bimerons have attracted a lot of attentions, because they have small
size and low depinning current, and can be used as nonvolatile information carries
in future spintronic devices. In this chapter, we mainly present and discuss recent
original results about the magnetization dynamics of antiferromagnetic skyrmions
and bimerons excited by currents and spatially non-uniform magnetic anisotropy. In
addition, we also explore possible applications based on antiferromagnetic skyrmions
and bimerons, and review some relevant results.
16.1 Introduction
Antiferromagnets are magnetically ordered spin systems, and antiferromagnetic
materials are promising for building advanced spintronic devices [1–4]. Considering
an antiferromagnet with two sublattices, its magnetization dynamics is governed
by the Landau-Lifshitz-Gilbert (LLG) equations [5], which can also describe the
dynamics of a ferromagnet. However, the dynamic equations of antiferromagnets are
coupled via the exchange interaction between sublattices, causing that the motion
equation of the order parameter is of second order with respect to time [2]. Thus, the
L. Shen · X. Liang · J. Xia · X. Zhang · Y. Zhou (B)
School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen 518172,
Guangdong, China
e-mail: zhouyan@cuhk.edu.cn
M. Ezawa
Department of Applied Physics, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656, Japan
O. A. Tretiakov
School of Physics, The University of New South Wales, Sydney 2052, Australia
© Springer Nature Switzerland AG 2021
E. Kamenetskii (ed.), Chirality, Magnetism and Magnetoelectricity,
Topics in Applied Physics 138,
https://doi.org/10.1007/978-3-030-62844-4_16
441
Antiferromagnetic Skyrmions
and Bimerons
Laichuan Shen, Xue Liang, Jing Xia, Xichao Zhang, Motohiko Ezawa,
Oleg A. Tretiakov, and Yan Zhou
Abstract The topological spin textures, such as magnetic skyrmions and bimerons,
are currently a hot topic in condensed matter physics. Magnetic skyrmions are
swirling spin textures, which can be stabilized in chiral magnets with perpendicular magnetic anisotropy, while magnetic bimerons can be regarded as the counterpart of skyrmions in magnetic systems with in-plane anisotropy. Both magnetic
skyrmions and bimerons have attracted a lot of attentions, because they have small
size and low depinning current, and can be used as nonvolatile information carries
in future spintronic devices. In this chapter, we mainly present and discuss recent
original results about the magnetization dynamics of antiferromagnetic skyrmions
and bimerons excited by currents and spatially non-uniform magnetic anisotropy. In
addition, we also explore possible applications based on antiferromagnetic skyrmions
and bimerons, and review some relevant results.
16.1 Introduction
Antiferromagnets are magnetically ordered spin systems, and antiferromagnetic
materials are promising for building advanced spintronic devices [1–4]. Considering
an antiferromagnet with two sublattices, its magnetization dynamics is governed
by the Landau-Lifshitz-Gilbert (LLG) equations [5], which can also describe the
dynamics of a ferromagnet. However, the dynamic equations of antiferromagnets are
coupled via the exchange interaction between sublattices, causing that the motion
equation of the order parameter is of second order with respect to time [2]. Thus, the
L. Shen · X. Liang · J. Xia · X. Zhang · Y. Zhou (B)
School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen 518172,
Guangdong, China
e-mail: zhouyan@cuhk.edu.cn
M. Ezawa
Department of Applied Physics, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656, Japan
O. A. Tretiakov
School of Physics, The University of New South Wales, Sydney 2052, Australia
© Springer Nature Switzerland AG 2021
E. Kamenetskii (ed.), Chirality, Magnetism and Magnetoelectricity,
Topics in Applied Physics 138,
https://doi.org/10.1007/978-3-030-62844-4_16
441