Abstract： Using a nonadiabatic evolution method, we investigate the spin filter effect in organic polymers in the presence of a local magnetic field. Through a spin-dependent magnetic field, polarons (charge carrier) with different spins will feel repulsive or attractive force determined by their spins. Our simulations show that in a single-site magnetic field (affecting electrons at a single site), for example V150=0.35eV, or V150=0.45eV, a spin-up polaron accelerated to saturated velocity by an electric field can pass through the field while the spin-down polaron is trapped. When the local field extends over several sites (Vn ～ exp[-(n-nc) sup>2/n2w]), similar behaviour is also found. Simultaneously we find that it is more likely to realize the spin filter effect in a comparatively large field since the polaron which feels attractive force is easily trapped by a local magnetic field.
YAN Yong-Hong;CHEN Mei-Juan;WU Chang-Qin. Spin Filter Effect in Organic Polymers in the Presence of Local Magnetic Field[J]. 中国物理快报, 2006, 23(9): 2549-2552.
YAN Yong-Hong, CHEN Mei-Juan, WU Chang-Qin. Spin Filter Effect in Organic Polymers in the Presence of Local Magnetic Field. Chin. Phys. Lett., 2006, 23(9): 2549-2552.
2006, Vol. 23 
