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Possible Localized Modes in the Uniform Quantum Heisenberg Chains of Sr2CuO3

J. P. Boucher·M. Takigawa
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Abstract

A model of mobile-bond defects is tentatively proposed to analyze the "anomalies" observed on the NMR spectrum of the quantum Heisenberg chains of Sr2CuO3. A bond-defect is a local change in the exchange coupling. It results in a local alternating magnetization (LAM), which when the defect moves, creates a flipping process of the local field seen by each nuclear spin. At low temperature, when the overlap of the LAM becomes large, the defects form a periodic structure, which extends over almost all the chains. In that regime, the density of bond-defects decreases linearly with T.

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J. P. Boucher, M. Takigawa. 2000-04-06. Possible Localized Modes in the Uniform Quantum Heisenberg Chains of Sr2CuO3. https://doi.org/10.1103/physrevb.62.367

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