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Two-stage spin-flop transitions in S = 1/2 antiferromagnetic spin chain BaCu_2Si_2O_7

I. Tsukada·J. Takeya·T. Masuda·K. Uchinokura
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Abstract

Two-stage spin-flop transitions are observed the in quasi-one-dimensional antiferromagnet, BaCu${}_2$Si${}_2$O${}_7$. A magnetic field applied along the easy axis induces a spin-flop transition at 2.0 T followed by a second transition at 4.9 T. The magnetic susceptibility indicates the presence of Dzyaloshinskii-Moriya (DM) antisymmetric interactions between the intrachain neighboring spins. We discuss a possible mechanism whereby the geometrical competition between DM and interchain interactions, as discussed for the two-dimensional antiferromagnet La${}_2$CuO${}_4$, causes the two-stage spin-flop transitions.

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I. Tsukada, J. Takeya, T. Masuda, K. Uchinokura. 2001-07-16. Two-stage spin-flop transitions in S = 1/2 antiferromagnetic spin chain BaCu_2Si_2O_7. https://doi.org/10.1103/physrevlett.87.127203

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