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Spin Gap in a Doped Kondo Chain

Arnold E. Sikkema·Ian Affleck·Steven R. White
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Abstract

We show that the Kondo chain away from half-filling has a spin gap upon the introduction of an additional direct Heisenberg coupling between localized spins. This is understood in the weak-Kondo-coupling limit of the Heisenberg-Kondo lattice model by bosonization and in the strong-coupling limit by a mapping to a modified t-J model. Only for certain ranges of filling and Heisenberg coupling does the spin gap phase extend from weak to strong coupling.

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Arnold E. Sikkema, Ian Affleck, Steven R. White. 1997-03-28. Spin Gap in a Doped Kondo Chain. https://doi.org/10.1103/physrevlett.79.929

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