Orbital Selective Directional Conductor in the Two Orbital Hubbard Model

Anamitra Mukherjee; Niravkumar D. Patel; Adriana Moreo; Elbio Dagotto

doi:10.1103/physrevb.93.085144

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arXiv · 1510.04902

Orbital Selective Directional Conductor in the Two Orbital Hubbard Model

Anamitra Mukherjee·Niravkumar D. Patel·Adriana Moreo·Elbio Dagotto

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Abstract

Employing a recently developed many-body technique that allows for the incorporation of thermal effects, the rich phase diagram of a two dimensional two orbital (degenerate $d_{xz}$ and $d_{yz}$) Hubbard model is presented varying temperature and the repulsion $U$. Our main result is the finding at intermediate $U$ of a novel antiferromagnetic orbital selective state where an effective dimensional reduction renders one direction insulating and the other metallic. Possible realizations of this state are discussed. In addition we also study nematicity above the Néel temperature. After a careful finite-size scaling analysis the nematicity temperature window appears to survive in the bulk limit although it is very narrow.

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Anamitra Mukherjee, Niravkumar D. Patel, Adriana Moreo, Elbio Dagotto. 2016-02-10. Orbital Selective Directional Conductor in the Two Orbital Hubbard Model. https://doi.org/10.1103/physrevb.93.085144

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