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arXiv · 1210.4625

Two channel orbital Kondo effect in quantum dot with SO(n) symmetry

T. Kuzmenko·K. Kikoin·Y. Avishai
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Abstract

A scenario for the formation of symmetry protected non-Fermi-liquid (NFL) Kondo effect (KE) with spin variable enumerating Kondo channels is suggested and worked out. In doubly occupied symmetric triple quantum dot within parallel geometry, the NFL low-energy regime arises provided the device possesses both source-drain and left-right parity. Kondo screening follows a multistage renormalization group mechanism: reduction of the energy scale is accompanied by the change of the relevant symmetry group from SO(8) to SO(5). At low energy, three phases compete: 1) under-screening spin triplet (conventional) KE; 2) spin singlet potential scattering; 3) NFL phase where the roles of spin and orbital degrees of freedom are swapped.

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T. Kuzmenko, K. Kikoin, Y. Avishai. 2013-08-30. Two channel orbital Kondo effect in quantum dot with SO(n) symmetry. https://doi.org/10.1103/physrevb.88.125102

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