Dynamical nuclear polarization in double quantum dots induced by hyperfine interaction

In this work the tunneling current through a weakly coupled DQDs in an external BDC is analyzed. We propose a model which includes hyperfine interaction. The time evolution for electronic charge occupations and for the nuclei polarizations in each dot is obtained by means of rate equations which are self-consistently solved. We analyze the current in the SB region as a function of BDC and observe hysteretic behavior for magnetic fields corresponding to the crossings between triplet and singlet states. Bistability is also produced for the induced nuclei spin polarizations within each quantum dot.