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arXiv · 1301.4235

Magnetic flux tuning of Fano-Kondo interplay in a parallel double quantum dot system

R. R. Agundez·J. Verduijn·S. Rogge·M. Blaauboer
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Abstract

We investigate the Fano-Kondo interplay in an Aharonov-Bohm ring with an embedded non-interacting quantum dot and a Coulomb interacting quantum dot. Using a slave-boson mean-field approximation we diagonalize the Hamiltonian via scattering matrix theory, and derive the conductance in the form of a Fano expression, which depends on the mean field parameters. We predict that in the Kondo regime the magnetic field leads to a gapped energy level spectrum due to hybridisation of the non-interacting QD state and the Kondo state, and can quantum-mechanically alter the electron's path preference. We demonstrate that an abrupt symmetry change in the Fano resonance, as seen experimentally, could be a consequence of an underlying Kondo channel.

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R. R. Agundez, J. Verduijn, S. Rogge, M. Blaauboer. 2013-01-17. Magnetic flux tuning of Fano-Kondo interplay in a parallel double quantum dot system. https://doi.org/10.1103/physrevb.87.235407

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