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arXiv:1006.4196 · Physical Review B

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

Bruce Normand, Christian Rüegg

Published Feb 14, 2011• 55 citations
arXivHTMLPDF

Abstract

The discovery of the almost ideal, two-chain spin-ladder material (C${}_{5}$H${}_{12}$N)${}_{2}$CuBr${}_{4}$ has once again focused attention on this most fundamental problem in low-dimensional quantum magnetism. With experimental data now available at all temperatures and magnetic fields, a correspondingly systematic theoretical description is required. This is obtained for the gapped regime within the bond-operator framework, by implementing three qualitative advances that account for triplet correlation effects, their evolution in a field, and the magnetization induced when both field and temperature are finite. Quantitative and parameter-free results are presented as experimental comparisons with the measured specific heat and as predictions for thermal renormalization of the triplet magnon excitations.

DOI
10.1103/physrevb.83.054415

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