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Phase transition in the one-dimensional Kondo lattice model with attractive electron-electron interaction

N. Shibata·M. Sigrist·E. Heeb
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Abstract

The one-dimensional Kondo lattice model with attractive interaction among the conduction electrons is analyzed in the case of half-filling. It is shown that there are three distinct phases depending on the coupling constants of the model. Two phases have a spin and charge gap. While one shows a clear separation of the spin and charge excitation spectrum the other phase may be characterized as a band insulator type where both excitations are due to two-particle states. The third phase is gapless in both channels and has quasi long-range order in the spin and charge density wave correlation. In this phase the spin and charge excitations have again a clearly separated spectrum. For the analysis we discuss first two limiting cases. Then a density matrix renormalization group calculation on finite systems is applied to determine the phase diagram and the correlation functions in the gapped and gapless phase for general couplding constants.

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N. Shibata, M. Sigrist, E. Heeb. 1997-04-28. Phase transition in the one-dimensional Kondo lattice model with attractive electron-electron interaction. https://doi.org/10.1103/physrevb.56.11084

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