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arXiv · 2410.04954

Observation of the spiral spin liquid in a triangular-lattice material

N. D. Andriushin·S. E. Nikitin·Ø. S. Fjellvåg·J. S. White·A. Podlesnyak·D. S. Inosov·M. C. Rahn·M. Schmidt·M. Baenitz·A. S. Sukhanov
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Abstract

The spiral spin liquid (SSL) is a highly degenerate state characterized by a continuous contour or surface in reciprocal space spanned by a spiral propagation vector. Although the SSL state has been predicted in a number of various theoretical models, very few materials are so far experimentally identified to host such a state. Via combined single-crystal wide-angle and small-angle neutron scattering, we report observation of the SSL in the quasi-two-dimensional delafossite AgCrSe$_2$. We show that it is a very close realization of the ideal Heisenberg $J_1$--$J_2$--$J_3$ frustrated model on the triangular lattice. By supplementing our experimental results with microscopic spin-dynamics simulations, we demonstrate how such exotic magnetic states are driven by thermal fluctuations and exchange frustration.

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N. D. Andriushin, S. E. Nikitin, Ø. S. Fjellvåg, J. S. White, A. Podlesnyak, D. S. Inosov, M. C. Rahn, M. Schmidt, M. Baenitz, A. S. Sukhanov. 2024-10-07. Observation of the spiral spin liquid in a triangular-lattice material. https://doi.org/10.1038/s41467-025-57319-2

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