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arXiv · 1903.12462

Putative spin-nematic phase in BaCdVO(PO$_{4}$)$_{2}$

M. Skoulatos·F. Rucker·G. J. Nilsen·A. Bertin·E. Pomjakushina·J. Ollivier·A. Schneidewind·R. Georgii·O. Zaharko·L. Keller·Ch. Rüegg·C. Pfleiderer·B. Schmidt·N. Shannon·A. Kriele·A. Senyshyn·A. Smerald
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Abstract

We report neutron scattering and AC magnetic susceptibility measurements of the 2D spin-1/2 frustrated magnet BaCdVO(PO$_{4}$)$_{2}$. At temperatures well below $T_{\sf N}\approx 1K$, we show that only 34 % of the spin moment orders in an up-up-down-down strip structure. Dominant magnetic diffuse scattering and comparison to published $\mu$sr measurements indicates that the remaining 66 % is fluctuating. This demonstrates the presence of strong frustration, associated with competing ferromagnetic and antiferromagnetic interactions, and points to a subtle ordering mechanism driven by magnon interactions. On applying magnetic field, we find that at $T=0.1$ K the magnetic order vanishes at 3.8 T, whereas magnetic saturation is reached only above 4.5 T. We argue that the putative high-field phase is a realization of the long-sought bond-spin-nematic state.

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M. Skoulatos, F. Rucker, G. J. Nilsen, A. Bertin, E. Pomjakushina, J. Ollivier, A. Schneidewind, R. Georgii, O. Zaharko, L. Keller, Ch. Rüegg, C. Pfleiderer, B. Schmidt, N. Shannon, A. Kriele, A. Senyshyn, A. Smerald. 2019-03-29. Putative spin-nematic phase in BaCdVO(PO$_{4}$)$_{2}$. https://doi.org/10.1103/physrevb.100.014405

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