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Double quantum dots: interdot interactions, co-tunneling, and Kondo resonances without spin

Qing-feng Sun·Hong Guo
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Abstract

We show that through an interdot off-site electron correlation in a double quantum-dot (DQD) device, Kondo resonances emerge in the local density of states without the electron spin-degree of freedom. We identify the physical mechanism behind this phenomenon: rather than forming a spin singlet in the device as required in the conventional Kondo physics, we found that exchange of electron position between the two quantum dots, together with the off-site Coulomb interaction, are sufficient to induce the Kondo resonance. Due to peculiar co-tunneling events, the Kondo resonance in one dot may be pinned at the chemical potential of the other one.

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Qing-feng Sun, Hong Guo. 2001-09-07. Double quantum dots: interdot interactions, co-tunneling, and Kondo resonances without spin. https://doi.org/10.1103/physrevb.66.155308

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