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Novel massless phase of Haldane-gap antiferromagnets in magnetic field

Gabor Fath·Peter B. Littlewood
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Abstract

The behavior of Haldane-gap antiferromagnets in strong magnetic field is not universal. While the low-energy physics of the conventional 1D spin-1 Heisenberg model in its magnetized regime is described by one incommensurate soft mode, other systems with somewhat perturbed coupling constants can possess two characteristic soft modes in a certain range of the field strength. Such a {\em two}-component Lutinger liquid phase is realised above the massive Haldane-gap phase, and in general above any massive nonmagnetic phase, when the ground state exhibits short range incommensurate fluctuations already in the absence of the field.

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Gabor Fath, Peter B. Littlewood. 1998-10-20. Novel massless phase of Haldane-gap antiferromagnets in magnetic field. https://doi.org/10.1103/physrevb.58.r14709

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