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arXiv · 1004.3834

Insulator-to-metal phase transition in Yb-based Kondo insulators

Guang-Bin Li·Guang-Ming Zhang·Lu Yu
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Abstract

The periodic Anderson lattice model for the crystalline electric field (CEF)split 4f quartet states is used to describe the Yb-based Kondo insulators/semiconductors. In the slave-boson mean-field approximation, we derive the hybridized quasiparticle bands, and find that decreasing the hybridization difference of the two CEF quartets may induce an insulator-to-metal phase transition. The resulting metallic phase has a hole and an electron Fermi pockets. Such a phase transition may be realized experimentally by applying pressure, reducing the difference in hybridization of the two CEF quartets.

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Guang-Bin Li, Guang-Ming Zhang, Lu Yu. 2010-04-22. Insulator-to-metal phase transition in Yb-based Kondo insulators. https://doi.org/10.1209/0295-5075%2F91%2F57002

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