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Quantum criticality in a double quantum-dot system

Gergely Zarand·Chung-Hou Chung·Pascal Simon·Matthias Vojta
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Abstract

We discuss the realization of the quantum-critical non-Fermi liquid state, originally discovered within the two-impurity Kondo model, in double quantum-dot systems. Contrary to the common belief, the corresponding fixed point is robust against particle-hole and various other asymmetries, and is only unstable to charge transfer between the two dots. We propose an experimental set-up where such charge transfer processes are suppressed, allowing a controlled approach to the quantum critical state. We also discuss transport and scaling properties in the vicinity of the critical point.

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Gergely Zarand, Chung-Hou Chung, Pascal Simon, Matthias Vojta. 2006-10-18. Quantum criticality in a double quantum-dot system. https://doi.org/10.1103/physrevlett.97.166802

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