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Two-channel Kondo Lattice Model on a ladder studied by the Density Matrix Renormalization Group Method

Juana Moreno·Shaojin Qin·P. Coleman·Lu Yu
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Abstract

Using the density matrix renormalization group (DMRG) method we study a two-channel Kondo lattice model on a half filled ladder. Our model involves an on-site s-wave and a nearest neighbor d-wave coupling between the local moments and the conduction electrons on the ladder. By changing the relative strength of the two Kondo interactions we examine the evolution of the system from a conventional Kondo insulator with a singlet at each site to a new kind of semimetallic state formed by overlapping of Zhang-Rice-like singlets. The DMRG is used to study how the spin and charge correlation functions evolve between these two regimes.

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Juana Moreno, Shaojin Qin, P. Coleman, Lu Yu. 2000-11-21. Two-channel Kondo Lattice Model on a ladder studied by the Density Matrix Renormalization Group Method. https://doi.org/10.1103/physrevb.64.085116

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