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arXiv · 1010.1551

Two-Stage Kondo Effect and Kondo Box Level Spectroscopy in a Carbon Nanotube

Yu. Bomze·I. Borzenets·H. Mebrahtu·A. Makarovski·H. U. Baranger·G. Finkelstein
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Abstract

The concept of the "Kondo box" describes a single spin, antiferromagnetically coupled to a quantum dot with a finite level spacing. Here, a Kondo box is formed in a carbon nanotube interacting with a localized electron. We investigate the spins of its first few eigenstates and compare them to a recent theory. In an 'open' Kondo-box, strongly coupled to the leads, we observe a non-monotonic temperature dependence of the nanotube conductance, which results from a competition between the Kondo-box singlet and the 'conventional' Kondo state that couples the nanotube to the leads.

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Yu. Bomze, I. Borzenets, H. Mebrahtu, A. Makarovski, H. U. Baranger, G. Finkelstein. 2010-10-07. Two-Stage Kondo Effect and Kondo Box Level Spectroscopy in a Carbon Nanotube. https://doi.org/10.1103/physrevb.82.161411

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