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New polarization effect and collective excitation in S=1/2 quasi 1D antiferromagnetic quantum spin chain

S. V. Demishev·A. V. Semeno·H. Ohta·S. Okubo·I. E. Tarasenko·T. V. Ishchenko·N. E. Sluchanko
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Abstract

Anomalous polarization characteristics of magnetic resonance in CuGeO3 doped with 2% of Co impurity are reported. For the Faraday geometry this mode is damped for the microwave field Bw aligned along a certain crystallographic direction showing that the character of magnetic oscillation differs from the standard spin precession. The observed resonance coexists with the ESR on Cu2+ chains and argued not to be caused by "impurity" EPR, as previously claimed, but to correspond to a previously unknown collective mode of magnetic oscillations in S=1/2 AF quantum spin chain.

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S. V. Demishev, A. V. Semeno, H. Ohta, S. Okubo, I. E. Tarasenko, T. V. Ishchenko, N. E. Sluchanko. 2006-09-01. New polarization effect and collective excitation in S=1/2 quasi 1D antiferromagnetic quantum spin chain. https://arxiv.org/abs/cond-mat/0609022

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