Spin-polarization Electron Transport Properties of the Narrow-wide-narrow Quantum Wire

In this paper,the arrow-wide-narrow form of the quantum wire is studied by lattice green function method.It was found that spin-orbital coupling can produce not only potential trap,but also bound states,which may result in Fano resonant conductance structure.The spin polarization rate is introduced by Fano resonance or antiresonance.In our model,when the spin-polarized electrons injected from the input lead,the electron spin polarization rate will be as high as the 0.99 in the output lead.And when the system structure parameters change,in the output lead,spin polarization rate will be changed periodically just like the form of sine function.