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arXiv · 1912.06309

Direct observation of cycloidal spin modulation and field-induced transition in N\'eel-type skyrmion-hosting VOSe$_2$O$_5$

T. Kurumaji·T. Nakajima·A. Feoktystov·E. Babcock·Z. Salhi·V. Ukleev·T. Arima·K. Kakurai·Y. Tokura
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Abstract

We investigate the spin rotational structure of magnetic skyrmions in a tetragonal polar magnet VOSe2O5 via polarized small-angle neutron scattering (SANS). Spin polarization analysis of the scattered neutrons provides consistent evidence for the cycloidal spin modulation in all the incommensurate phases at zero and non-zero magnetic field along the c axis, including the triangular skyrmion-lattice phase. In the vicinity of the skyrmion phase, we performed extensive SANS measurements to unravel a field-induced incommensurate phase (IC-2 state). We discuss the possibility of anisotropic double-q state as an alternative spin structure to provisional square skyrmion-lattice state.

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T. Kurumaji, T. Nakajima, A. Feoktystov, E. Babcock, Z. Salhi, V. Ukleev, T. Arima, K. Kakurai, Y. Tokura. 2019-12-13. Direct observation of cycloidal spin modulation and field-induced transition in N\'eel-type skyrmion-hosting VOSe$_2$O$_5$. https://doi.org/10.7566/jpsj.90.024705

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