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Zero-Bias Conductance Through Side-Coupled Double Quantum Dots

J. Bonca·R. Zitko
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Abstract

Low temperature zero-bias conductance through two side-coupled quantum dots is investigated using Wilson's numerical renormalization group technique. A low-temperature phase diagram is computed. Near the particle-hole symmetric point localized electrons form a spin-singlet associated with weak conductance. For weak inter-dot coupling we find enhanced conductance due to the two-stage Kondo effect when two electrons occupy quantum dots. When quantum dots are populated with a single electron, the system enters Kondo regime with enhanced conductance. Analytical expressions for the width of the Kondo regime and the Kondo temperature in this regime are given.

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J. Bonca, R. Zitko. 2006-02-16. Zero-Bias Conductance Through Side-Coupled Double Quantum Dots. https://doi.org/10.1007/978-1-4020-5659-8_29

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