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Gate voltage effects in capacitively coupled quantum dots

Andrew K. Mitchell·Martin R. Galpin·David E. Logan
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Abstract

We study a system of two symmetrical capacitively coupled quantum dots, each coupled to its own metallic lead, focusing on its evolution as a function of the gate voltage applied to each dot. Using the numerical renormalization group and poor man's scaling techniques, the low-energy Kondo scale of the model is shown to vary significantly with the gate voltage, being exponentially small when spin and pseudospin degrees of freedom dominate; but increasing to much larger values when the gate voltage is tuned close to the edges of the Coulomb blockade staircase where low-energy charge-fluctuations also enter, leading thereby to correlated electron physics on energy/temperature scales more accessible to experiment. This range of behaviour is also shown to be manifest strongly in single-particle dynamics and electron transport through each dot.

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Andrew K. Mitchell, Martin R. Galpin, David E. Logan. 2006-11-08. Gate voltage effects in capacitively coupled quantum dots. https://doi.org/10.1209/epl%2Fi2006-10219-1

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