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arXiv · 1902.00954

Degenerate orbital effect in a three orbital periodic Anderson model

Jianwei Yang·Qiyu Wang·Tianxing Ma·Qiaoni Chen
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Abstract

The competition between the Ruderman-Kittel-Kasuya-Yosida effect and Kondo effect is a central subject of periodic Anderson model. By using the density matrix embedding theory, we study a three orbital periodic Anderson model, in which the effects of degenerate conduction orbitals via the local magnetic moments, number of electrons, and spin-spin correlation functions, are investigated. From the phase diagram at half filling, we find there exists two different anti-ferromagnetic phases and one paramagnetic phase. To explore the difference of the two anti-ferromagnetic phases, the topology of Fermi surface and the connection with standard periodic Anderson model are considered. The spin-spin correlation functions yield insight into the competition between Ruderman-Kittel-Kasuya-Yosida interaction and Kondo interaction. We further find there is a "scaling transformation" connects different ratio of the hybridization strength.

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Jianwei Yang, Qiyu Wang, Tianxing Ma, Qiaoni Chen. 2019-06-25. Degenerate orbital effect in a three orbital periodic Anderson model. https://doi.org/10.1103/physrevb.99.245136

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