Role of Dynamic Nuclear Polarization on the Transport Through Weakly Coupled Double Quantum Dots

We study the electronic transport through a weakly coupled double quantum dot in the spin blockade (SB) regime. These systems show leakage currents that have been attributed to hyperfine (HF) interactions. We model weakly coupled double-dot transport using a rate equation approach which accounts for HF flip-flop transitions. The rate equations allow us to obtain self-consistently the time evolution for electronic charge occupations and for the nuclei polarizations in each dot. We analyse the current in the SB region as a function of magnetic field and source&-drain voltage. We observe current steps for both variables corresponding to the crossings between triplet and singlet states. Hysteretic behaviour has also been observed.

Role of Dynamic Nuclear Polarization on the Transport Through Weakly Coupled Double Quantum Dots Articles