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arXiv · 2204.10682

Spin Density Wave versus Fractional Magnetization Plateau in a Triangular Antiferromagnet

L. Facheris·K. Yu. Povarov·S. D. Nabi·D. G. Mazzone·J. Lass·B. Roessli·E. Ressouche·Z. Yan·S. Gvasaliya·A. Zheludev
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Abstract

We report an excellent realization of the highly non-classical incommensurate spin-density wave (SDW) state in the quantum frustrated antiferromagnetic insulator Cs$_2$CoBr$_4$. In contrast to the well-known Ising spin chain case, here the SDW is stabilized by virtue of competing planar in-chain anisotropies and frustrated interchain exchange. Adjacent to the SDW phase is a broad $m = 1/3$ magnetization plateau that can be seen as a commensurate locking of the SDW state into the up-up-down (UUD) spin structure. This represents the first example of long-sought SDW-UUD transition in triangular-type quantum magnets.

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L. Facheris, K. Yu. Povarov, S. D. Nabi, D. G. Mazzone, J. Lass, B. Roessli, E. Ressouche, Z. Yan, S. Gvasaliya, A. Zheludev. 2022-04-22. Spin Density Wave versus Fractional Magnetization Plateau in a Triangular Antiferromagnet. https://doi.org/10.1103/physrevlett.129.087201

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