Hyperfine coupling of electron spins to nuclear spins is studied for a GaAs-based double quantum dot in the spin blockade regime where the electron conduction is mostly blocked by Pauli effect unless the electron spin state in the double dot is changed. A current flowing through the double dot shows time-dependent oscillations with a period of as long as 200 sec in a certain DC magnetic field range. The oscillatory behavior is significantly diminished by application of an AC magnetic field whose frequency can induce nuclear magnetic resonance for 71Ga and 69Ga, respectively. A possible nuclear spin polarization mechanism due to hyperfine flip-flop scattering is proposed.
@article{arxiv.cond-mat/0309062,
title = {Nuclear spin induced oscillatory current in spin-blocked quantum dots},
author = {Keiji Ono and Seigo Tarucha},
journal= {arXiv preprint arXiv:cond-mat/0309062},
year = {2009}
}