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Electron Spin Resonance in sine-Gordon spin chains in the perturbative spinon regime

S. A. Zvyagin·A. K. Kolezhuk·J. Krzystek·R. Feyerherm
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Abstract

We report the low-temperature multi-frequency ESR studies of copper pyrimidine dinitrate, a spin-1/2 antiferromagnetic chain with alternating $g$-tensor and the Dzyaloshinskii-Moriya interaction, allowing us to test a new theoretical concept proposed recently by Oshikawa and Affleck [Phys. Rev. Lett. 82, 5136 (1999)]. Their theory, based on bosonization and the self-energy formalism, can be applied for precise calculation of ESR parameters of $S=1/2$ antiferromagnetic chains in the perturbative spinon regime. Excellent quantitative agreement between the theoretical predictions and experiment is obtained.

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S. A. Zvyagin, A. K. Kolezhuk, J. Krzystek, R. Feyerherm. 2005-05-20. Electron Spin Resonance in sine-Gordon spin chains in the perturbative spinon regime. https://doi.org/10.1103/physrevlett.95.017207

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