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Quantum Antiferromagnets in a Magnetic Field

Daniel Loss·B. Normand
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Abstract

Motivated by recent experiments on low-dimensional quantum magnets in applied magnetic fields, we present a theoretical analysis of their properties based on the nonlinear sigma model. The spin stiffness and a 1/N expansion are used to map the regimes of spin-gap behavior, predominantly linear magnetization, and spin saturation. A two-parameter renormalization-group study gives the characteristic properties over the entire parameter range. The model is relevant to many systems exhibiting Haldane physics, and is applied here to the two-chain spin ladder compound CuHpCl.

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Daniel Loss, B. Normand. 1998-04-15. Quantum Antiferromagnets in a Magnetic Field. https://arxiv.org/abs/cond-mat/9804151

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