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Theory of Low Temperature Electron Spin Resonance in Half-integer Spin Antiferromagnetic Chains

Masaki Oshikawa·Ian Affleck
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Abstract

A theory of low temperature (T) electron spin resonance (ESR) in half-integer spin antiferromagnetic chains is developed using field theory methods and avoiding previous approximations. It is compared to experiments on Cu benzoate. Power laws are predicted for the line-width broadening due to various types of anisotropy. At T -> 0, zero width absorption peaks occur in some cases. The second ESR peak in Cu benzoate, observed at T<.76K, is argued not to indicate Neel order as previously claimed, but to correspond to a sine-Gordon "breather" excitation.

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Masaki Oshikawa, Ian Affleck. 1999-04-15. Theory of Low Temperature Electron Spin Resonance in Half-integer Spin Antiferromagnetic Chains. https://doi.org/10.1103/physrevlett.82.5136

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