Coupled charge-Kondo quantum dot devices*

Exquisite experimental control over exotic states of quantum matter has recently been demonstrated in charge-Kondo quantum dot devices [1,2]. These systems constitute a new paradigm for circuit realizations of fundamental models of quantum criticality, with essentially perfect agreement between experiment and theory for fractionalized two-channel and three-channel Kondo physics [2,3].

Here we study theoretically a device comprising two charge-Kondo quantum dots, coupled together by a quantum point contact. This system is the first step towards constructing more elaborate nanodevices using charge-Kondo building blocks, which could eventually lead to quantum simulations of exotic lattice models.

Depending on dot occupation, different variants on the classic two-impurity Kondo model can be realized, and clear signatures of quantum criticality show up in measurable conductance as a function of tunable parameters.

[1] Iftikhar et al, Nature 526, 233 (2015)
[2] Iftikhar et al, Science 360, 1315 (2018)
[3] Mitchell et al, PRL 157202 (2016)