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Electron spin resonance in high-field critical phase of gapped spin chains

A. K. Kolezhuk·H. -J. Mikeska
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Abstract

Motivated by recent experiments on Ni(C_{2}H_{8}N_{2})_{2}Ni(CN)_{4} (commonly known as NENC), we study the electron spin resonance in the critical high-field phase of the antiferromagnetic S=1 chain with strong planar anisotropy and show that the ESR spectra exhibit several peculiarities in the critical phase. Possible relevance of those results for other gapped spin systems is discussed.

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A. K. Kolezhuk, H. -J. Mikeska. 2001-05-27. Electron spin resonance in high-field critical phase of gapped spin chains. https://doi.org/10.1103/physrevb.65.014413

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