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arXiv · 1710.04000

Néel-type skyrmion lattice in tetragonal polar magnet VOSe$_2$O$_5$

Takashi Kurumaji·Taro Nakajima·Victor Ukleev·Artem Feoktystov·Taka-hisa Arima·Kazuhisa Kakurai·Yoshinori Tokura
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Abstract

Formation of the triangular skyrmion-lattice is found in a tetragonal polar magnet VOSe$_2$O$_5$. By magnetization and small-angle neutron scattering measurements on the single crystals, we identify a cycloidal spin state at zero field and a Néel-type skyrmion-lattice phase under a magnetic field along the polar axis. Adjacent to this phase, another magnetic phase of an incommensurate spin texture is identified at lower temperatures, tentatively assigned to a square skyrmion-lattice phase. These findings exemplify the versatile features of Néel-type skyrmions in bulk materials, and provide a unique occasion to explore the physics of topological spin textures in polar magnets.

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Takashi Kurumaji, Taro Nakajima, Victor Ukleev, Artem Feoktystov, Taka-hisa Arima, Kazuhisa Kakurai, Yoshinori Tokura. 2017-10-11. Néel-type skyrmion lattice in tetragonal polar magnet VOSe$_2$O$_5$. https://doi.org/10.1103/physrevlett.119.237201

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