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arXiv · 1912.06399

Magnetic spiral order in the square-lattice spin system (CuBr)Sr$_{2}$Nb$_{3}$O$_{10}$

A. V. Mikheyenkov·V. E. Valiulin·A. F. Barabanov
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Abstract

We address quantum spin helical states in the strongly frustrated Heisenberg model. Contrary to conventional Dzyaloshinskii-Moriya approach we show that such states appear without central symmetry breaking. As an example, we demonstrate that the magnetic and thermodynamic properties of the quasi-two-dimensional square-lattice compound $\mathrm{(CuBr)Sr_{2}Nb_{3}O_{10}}$ can be interpreted within 2D $S = 1/2$ $J_1-J_2-J_3$ Heisenberg model. In this compound neutron experiment indicates helical spin order while central symmetry does hold.

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A. V. Mikheyenkov, V. E. Valiulin, A. F. Barabanov. 2019-12-13. Magnetic spiral order in the square-lattice spin system (CuBr)Sr$_{2}$Nb$_{3}$O$_{10}$. https://doi.org/10.1016/j.physb.2020.412533

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