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arXiv · 0705.4537

Correlation Effects in Side-Coupled Quantum Dots

Rok Zitko Janez Bonca
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Abstract

Using Wilson's numerical renormalization group (NRG) technique we compute zero-bias conductance and various correlation functions of a double quantum dot (DQD) system. We present different regimes within a phase diagram of the DQD system. By introducing a negative Hubbard U on one of the quantum dots, we simulate the effect of electron-phonon coupling and explore the properties of the coexisting spin and charge Kondo state. In a triple quantum dot (TQD) system a multi-stage Kondo effect appears where localized moments on quantum dots are screened successively at exponentially distinct Kondo temperatures.

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Rok Zitko Janez Bonca. 2007-05-31. Correlation Effects in Side-Coupled Quantum Dots. https://doi.org/10.1088/0953-8984%2F19%2F25%2F255205

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