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arXiv · 1608.04495

Exchange anisotropy as mechanism for spin-stripe formation in frustrated spin chains

M. Pregelj·O. Zaharko·M. Herak·M. Gomilsek·A. Zorko·L. C. Chapon·F. Bourdarot·H. Berger·D. Arčon
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Abstract

We investigate the spin-stripe mechanism responsible for the peculiar nanometer modulation of the incommensurate magnetic order that emerges between the vector-chiral and the spin-density-wave phase in the frustrated zigzag spin-1/2 chain compound $β$-TeVO$_4$. A combination of magnetic-torque, neutron-diffraction and spherical-neutron-polarimetry measurements is employed to determine the complex magnetic structures of all three ordered phases. Based on these results, we develop a simple phenomenological model, which exposes the exchange anisotropy as the key ingredient for the spin-stripe formation in frustrated spin systems.

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M. Pregelj, O. Zaharko, M. Herak, M. Gomilsek, A. Zorko, L. C. Chapon, F. Bourdarot, H. Berger, D. Arčon. 2016-08-30. Exchange anisotropy as mechanism for spin-stripe formation in frustrated spin chains. https://doi.org/10.1103/physrevb.94.081114

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