Spin pump effects on the spin current through two coupled quantum dots H. Pan, S.-Q. Duan, L.-N. Zhao, W.-D. Chu and W. Zhang Eur. Phys. J. B, 62 1 (2008) 71-76 Published online: 28 March 2008 DOI: 10.1140/epjb/e2008-00130-1