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arXiv · 1203.4692

Electric Dipolar Kondo Effect Emerging from Vibrating Magnetic Ion

Takashi Hotta·Kazuo Ueda
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Abstract

When a magnetic ion vibrates in a metal, it inevitably introduces a new channel of hybridization with conduction electrons and in general, the vibrating ion induces electric dipole moment. In such a situation, we find that magnetic and non-magnetic Kondo effects alternatively occur due to the screening of spin moment and electric dipole moment of vibrating ion. In particular, electric dipolar two-channel Kondo effect is found to occur for weak Coulomb interaction. We also show that magnetically robust heavy-electron state appears near the fixed point of electric dipolar two-channel Kondo effect. We believe that the {\it vibrating} magnetic ion opens a new door in the Kondo physics.

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Takashi Hotta, Kazuo Ueda. 2012-03-21. Electric Dipolar Kondo Effect Emerging from Vibrating Magnetic Ion. https://doi.org/10.1103/physrevlett.108.247214

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