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arXiv · 1006.4196

Complete bond-operator theory of the two-chain spin ladder

B. Normand·Ch. Rüegg
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Abstract

The discovery of the almost ideal, two-chain spin-ladder material (C_5H_12N)_2CuBr_4 has once again focused attention on this most fundamental problem in low-dimensional quantum magnetism. Within the bond-operator framework, three qualitative advances are introduced which extend the theory to all finite temperatures and magnetic fields in the gapped regime. This systematic description permits quantitative and parameter-free experimental comparisons, which are presented for the specific heat, and predictions for thermal renormalization of the triplet magnon excitations.

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B. Normand, Ch. Rüegg. 2010-06-22. Complete bond-operator theory of the two-chain spin ladder. https://doi.org/10.1103/physrevb.83.054415

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