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arXiv · 1212.6308

ESR of coupled spin-1/2 chains: unveiling zig-zag-type interchain correlations

A. A. Validov·M. Ozerov·J. Wosnitza·S. A. Zvyagin·M. M. Turnbull·C. P. Landee·G. B. Teitel'baum
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Abstract

By means of electron spin resonance investigations we revealed the crucial role of the interchain coupling in the spin dynamics of the spin-1/2 Heisenberg antiferromagnetic (AF) chain material copper-pyrazine-dinitrate, Cu(C$_4$H$_4$N$_2$)(NO$_3$)$_2$. We found that the dominating interchain interaction is of a zig-zag type. This interaction gives rise to geometrical frustration effects and strongly influences the character of AF ordering. Combining our experimental findings with the results of a quasiclassical approach we argue that at low temperatures the system orders in an incommensurate spiral state.

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A. A. Validov, M. Ozerov, J. Wosnitza, S. A. Zvyagin, M. M. Turnbull, C. P. Landee, G. B. Teitel'baum. 2012-12-27. ESR of coupled spin-1/2 chains: unveiling zig-zag-type interchain correlations. https://arxiv.org/abs/1212.6308

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