Correlation effects in side-coupled quantum dots

Abstract

Using Wilson’s numerical renormalization group (NRG) technique, we compute zero-biasconductance and various correlation functions of a double quantum dot (DQD) system. We presentdifferent regimes within a phase diagram of the DQD system. By introducing a negative HubbardU on one of the quantum dots, we simulate the effect of electron–phonon coupling and explorethe 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 quantumdots are screened successively at exponentially distinct Kondo temperatures.