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arXiv · 0807.3641

Dynamical Dzyaloshinsky-Moriya Interaction in KCuF3

M. V. Eremin·D. V. Zakharov·H. -A. Krug von Nidda·R. M. Eremina·A. Shuvaev·A. Pimenov·P. Ghigna·J. Deisenhofer·A. Loidl
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Abstract

The spin dynamics of the prototypical quasi one-dimensional antiferromagnetic Heisenberg spin S=1/2 chain KCuF3 is investigated by electron spin resonance spectroscopy. Our analysis shows that the peculiarities of the spin dynamics require a new dynamical form of the antisymmetric anisotropic spin-spin interaction. This dynamical Dzyaloshinsky-Moriya interaction is related to strong oscillations of the bridging fuorine ions perpendicular to the crystallographic c axis. This new mechanism allows to resolve consistently the controversies in observation of the magnetic and structural properties of this orbitally ordered perovskite compound.

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M. V. Eremin, D. V. Zakharov, H. -A. Krug von Nidda, R. M. Eremina, A. Shuvaev, A. Pimenov, P. Ghigna, J. Deisenhofer, A. Loidl. 2008-07-23. Dynamical Dzyaloshinsky-Moriya Interaction in KCuF3. https://doi.org/10.1103/physrevlett.101.147601

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