Transport in quantum spin Hall edges in contact to a quantum dot

RIZZO, BRUNO; ARRACHEA, LILIANA; CAMJAYI, ALBERTO

PHYSICAL REVIEW B

AMER PHYSICAL SOC

Año: 2016 vol. 94

1098-0121

We study the transport mechanisms taking place in a quantum spin Hall bar with an embedded quantum dot, where electrons localize and experience Coulomb interaction U as well as spin-flip processes λ. We solve the problem with nonequilibrium Green functions. We focus on the linear-response regime and treat the many-body interactions with quantum Monte Carlo. The effects of U and λ are competitive and the induced transport takes place through different channels. The two mechanisms can be switched by changing the occupation of the dot with a gate voltage.