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arXiv · 2309.09091

Anisotropy of Antiferromagnetic Domains in a Spin-orbit Mott Insulator

Longlong Wu·Wei Wang·Tadesse A. Assefa·Ana F. Suzana·Jiecheng Diao·Hengdi Zhao·Gang Cao·Ross J. Harder·Wonsuk Cha·Kim Kisslinger·Mark P. M. Dean·Ian K. Robinson
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Abstract

The temperature-dependent behavior of magnetic domains plays an essential role in the magnetic properties of materials, leading to widespread applications. However, experimental methods to access the three-dimensional (3D) magnetic domain structures are very limited, especially for antiferromagnets. Over the past decades, the spin-orbit Mott insulator iridate $Sr_2IrO_4$ has attracted particular attention because of its interesting magnetic structure and analogy to superconducting cuprates. Here, we apply resonant x-ray magnetic Bragg coherent diffraction imaging to track the real-space 3D evolution of antiferromagnetic ordering inside a $Sr_2IrO_4$ single crystal as a function of temperature, finding that the antiferromagnetic domain shows anisotropic changes. The anisotropy of the domain shape reveals the underlying anisotropy of the antiferromagnetic coupling strength within $Sr_2IrO_4$. These results demonstrate the high potential significance of 3D domain imaging in magnetism research.

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Longlong Wu, Wei Wang, Tadesse A. Assefa, Ana F. Suzana, Jiecheng Diao, Hengdi Zhao, Gang Cao, Ross J. Harder, Wonsuk Cha, Kim Kisslinger, Mark P. M. Dean, Ian K. Robinson. 2023-09-16. Anisotropy of Antiferromagnetic Domains in a Spin-orbit Mott Insulator. https://doi.org/10.1103/physrevb.108.l020403

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