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Doping of a spin-1 chain: integrable model

Holger Frahm·Markus P. Pfannmüller·A. M. Tsvelik
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Abstract

An exactly soluble model describing a spin S=1 antiferromagnetic chain doped with mobile S=1/2 carriers is constructed. In its continuum limit the undoped state is described by three gapless Majorana fermions composing the SU(2) triplet. Doping adds to this a scalar charge field and a singlet Majorana fermion with different velocity. We argue that this mode survives when the Haldane gap is added.

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Holger Frahm, Markus P. Pfannmüller, A. M. Tsvelik. 1998-08-13. Doping of a spin-1 chain: integrable model. https://doi.org/10.1103/physrevlett.81.2116

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