%A Wang Rui(王瑞), Zhang Cun-Xi(张存喜), Zhou Yun-Qing(周运清), and Kong Ling-Min(孔令民) %T Superexchange interaction enhancement of the quantum transport in a DNA-type molecule %0 Journal Article %D 2011 %J Chin. Phys. B %R 10.1088/1674-1056/20/11/117201 %P 117201-117201 %V 20 %N 11 %U {https://cpb.iphy.ac.cn/CN/abstract/article_112447.shtml} %8 2011-11-15 %X We use the transfer matrix method and the Green function technique to theoretically study the quantum tunnelling through a DNA-type molecule. Ferromagnetic electrodes are used to produce the spin-polarized transmission probability and therefore the spin current. The distance-dependent crossover comes from the topological variation from the one-dimensional to the two-dimensional model transform as we switch on the interstrand coupling; a new base pair will present N-1 extrachannels for the charge and spin as N being the total base pairs. This will restrain the decay of the transmission and improve the stability of the quantum transport. The spin and charge transfer through the DNA-type molecule is consistent with the quantum tunneling barrier.