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arXiv · 1206.1359

Cotunneling renormalization in carbon nanotube quantum dots

Gediminas Kiršanskas·Jens Paaske·Karsten Flensberg
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Abstract

We determine the level-shifts induced by cotunneling in a Coulomb blockaded carbon nanotube quantum dot using leading order quasi-degenerate perturbation theory within a single nanotube quartet. It is demonstrated that otherwise degenerate and equally tunnel-coupled $K$ and $K'$ states are mixed by cotunneling and therefore split up in energy except at the particle/hole-symmetric midpoints of the Coulomb diamonds. In the presence of an external magnetic field, we show that cotunneling induces a gate-dependent $g$-factor renormalization, and we outline different scenarios which might be observed experimentally, depending on the values of both intrinsic $KK'$ splitting and spin-orbit coupling.

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Gediminas Kiršanskas, Jens Paaske, Karsten Flensberg. 2012-06-06. Cotunneling renormalization in carbon nanotube quantum dots. https://doi.org/10.1103/physrevb.86.075452

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