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Exact Insulating and Conducting Ground States of a Periodic Anderson Model in Three Dimensions

Zsolt Gulacsi·Dieter Vollhardt
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Abstract

We present a class of exact ground states of a three-dimensional periodic Anderson model at 3/4 filling. Hopping and hybridization of d and f electrons extend over the unit cell of a general Bravais lattice. Employing novel composite operators combined with 55 matching conditions the Hamiltonian is cast into positive semidefinite form. A product wave function in position space allows one to identify stability regions of an insulating and a conducting ground state. The metallic phase is a non-Fermi liquid with one dispersing and one flat band.

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Zsolt Gulacsi, Dieter Vollhardt. 2003-02-11. Exact Insulating and Conducting Ground States of a Periodic Anderson Model in Three Dimensions. https://doi.org/10.1103/physrevlett.91.186401

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