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Phase Diagram of the Two-Leg Kondo Ladder

J. C. Xavier·E. Miranda·E. Dagotto
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Abstract

The phase diagram of the two-leg Kondo ladder is investigated using computational techniques. Ferromagnetism is present, but only at small conduction electron densities and robust Kondo coupling $J$. For densities $n\gtrsim0.4$ and any Kondo coupling, a paramagnetic phase is found. We also observed spin dimerization at densities $n$=1/4 and $n$=1/2. The spin structure factor at small $J$ peaks at $\vec{q}$=$(2n,0)π$ for $n\lesssim0.5$, and at $\vec{q}$=$(n,1)π$ for $n\gtrsim0.5$. The charge structure factor suggests that electrons behave as free particles with spin-1/2 (spin-0) for small (large) $J$.

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J. C. Xavier, E. Miranda, E. Dagotto. 2004-11-27. Phase Diagram of the Two-Leg Kondo Ladder. https://doi.org/10.1103/physrevb.70.172415

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