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arXiv · 0704.1722

Fermi Surface Reconstruction without Breakdown of Kondo Screening at Quantum Critical Point

Hiroshi Watanabe·Masao Ogata
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Abstract

Motivated by recent Hall-effect experiment in YbRh$_2$Si$_2$, we study ground state properties of a Kondo lattice model in a two-dimensional square lattice using variational Monte Carlo method. We show that there are two types of phase transition, antiferromagnetic transition and topological one (Fermi surface reconstruction). In a wide region of parameters, these two transitions occur simultaneously without the breakdown of Kondo screening, accompanied by a discontinuous change of the Hall coefficient. This result is consistent with the experiment and gives a novel theoretical picture for the quantum critical point in heavy fermion systems.

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Hiroshi Watanabe, Masao Ogata. 2007-04-13. Fermi Surface Reconstruction without Breakdown of Kondo Screening at Quantum Critical Point. https://doi.org/10.1103/physrevlett.99.136401

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