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Enhanced Two-Channel Kondo Physics in a Quantum Box Device

Paata Kakashvili·Henrik Johannesson
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Abstract

We propose a design for a one-dimensional quantum box device where the charge fluctuations are described by an anisotropic two-channel Kondo model. The device consists of a quantum box in the Coulomb blockade regime, weakly coupled to a quantum wire by a single-mode point contact. The electron correlations in the wire produce strong back scattering at the contact, significantly increasing the Kondo temperature as compared to the case of non-interacting electrons. By employing boundary conformal field theory techniques we show that the differential capacitance of the box exhibits manifest two-channel Kondo scaling with temperature and gate voltage, uncontaminated by the one-dimensional electron correlations. We discuss the prospect to experimentally access the Kondo regime with this type of device.

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Paata Kakashvili, Henrik Johannesson. 2007-09-02. Enhanced Two-Channel Kondo Physics in a Quantum Box Device. https://doi.org/10.1209/0295-5075%2F79%2F47004

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