We investigate the triplet-singlet relaxation in a double quantum dot defined by top-gates in an InAs nanowire. In the Pauli spin blockade regime, the leakage current can be mainly attributed to spin relaxation. While at weak and strong inter-dot coupling relaxation is dominated by two individual mechanisms, the relaxation is strongly reduced at intermediate coupling and finite magnetic field. In addition we observe a charateristic bistability of the spin-non conserving current as a function of magnetic field. We propose a model where these features are explained by the polarization of nuclear spins enabled by the interplay between hyperfine and spin-orbit mediated relaxation.
@article{arxiv.cond-mat/0701054,
title = {Suppression of spin relaxation in an InAs nanowire double quantum dot},
author = {A. Pfund and I. Shorubalko and K. Ensslin and R. Leturcq},
journal= {arXiv preprint arXiv:cond-mat/0701054},
year = {2009}
}