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Bond operator mean field theory of the half filled Kondo lattice model

Christoph Jurecka·Wolfram Brenig
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Abstract

We present a bond-operator mean field theory for the Kondo lattice model at half filling in two (2D) and three (3D) dimensions. A continuous quantum phase transition from an antiferromagnetic to a spin-gapped singlet ground state is found at J/t=1.505 (1.833) in 2D (3D). Additionally we evaluate the quasiparticle dispersions as well as the staggered magnetic moment and provide a comparison with complementary numerical approaches.

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Christoph Jurecka, Wolfram Brenig. 2001-03-24. Bond operator mean field theory of the half filled Kondo lattice model. https://doi.org/10.1103/physrevb.64.092406

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