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arXiv · 1408.4935

A Model for Two-Channel Kondo Effect in CNT Quantum Dot

Igor Kuzmenko·Tetyana Kuzmenko·Yshai Avishai
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Abstract

Over-screened Kondo effect is feasible in carbon nanotube quantum dot junction hosting a spin $\tfrac{1}{2}$ atom with single $s$-wave valence electron (e.g Au). The idea is to use the two valleys as two symmetry protected flavor quantum numbers $\xi={\bf K}, {\bf K}'$. Perturbative RG analysis exposes the finite weak-coupling two-channel fixed point, where the Kondo temperature is estimated to be around $0.5\div5$~K. Remarkably, occurrence of two different scaling regimes implies a non-monotonic dependence of the conductance as function of temperature.

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Igor Kuzmenko, Tetyana Kuzmenko, Yshai Avishai. 2014-08-21. A Model for Two-Channel Kondo Effect in CNT Quantum Dot. https://arxiv.org/abs/1408.4935

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