Brownian pump induced by the phase difference between the potential and the entropic barrierXin-tong Zheng, Jian-chun Wu, Bao-quan Ai and Feng-guo LiEur. Phys. J. B, 86 11 (2013) 479DOI: https://doi.org/10.1140/epjb/e2013-40862-y