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arXiv · 1107.4401

Carrier doping to a partially disordered state in the periodic Anderson model on a triangular lattice

Satoru Hayami·Masafumi Udagawa·Yukitoshi Motome
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Abstract

We investigate the effect of hole and electron doping to half-filling in the periodic Anderson model on a triangular lattice by the Hartree-Fock approximation at zero temperature. At half-filling, the system exhibits a partially disordered insulating state, in which a collinear antiferromagnetic order on an unfrustrated honeycomb subnetwork coexists with nonmagnetic state at the remaining sites. We find that the carrier doping destabilizes the partially disordered state, resulting in a phase separation to a doped metallic state with different magnetic order. The partially disordered state is restricted to the half-filled insulating case, while its metallic counterpart is obtained as a metastable state in a narrow electron doped region.

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Satoru Hayami, Masafumi Udagawa, Yukitoshi Motome. 2011-07-22. Carrier doping to a partially disordered state in the periodic Anderson model on a triangular lattice. https://doi.org/10.1088/1742-6596/400/3/032018

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