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Anti-Kondo regime of charge transport through a double dot molecule

Richard Berkovits·Boris Altshuler
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Abstract

The conductance through a serial double dot structure for which the inter-dot tunneling is stronger than the tunneling to the leads is studied using the numerical density matrix renormalization group method and analytic arguments. When the dots are occupied by 1 or 3 electrons the usual Kondo peak is obtained. For the case in which 2 electrons occupy the molecule a singlet is formed. Nevertheless, the conductance in that case has a constant non-zero value, and might even be equal to the maximum conductance of $2 e^2/h$ for certain values of the molecule parameters. We show that this is the result of the subtle interplay between the symmetric and anti-symmetric orbitals of the molecule caused by interactions and interference.

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Richard Berkovits, Boris Altshuler. 2006-10-19. Anti-Kondo regime of charge transport through a double dot molecule. https://arxiv.org/abs/cond-mat/0610466

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