Abstract :
Based on anisomerous double δ - magnetic - barrier nanostructure, an electron-spin filter can be formed [M.W. Lu, Appl. Surf. Sci. 252 (2005) 1747]. To structurally manipulate the spin polarization in spin filter, we dope a tunable δ - potential into the device by using modern material growth techniques such as molecular beam epitaxy. It is shown that the degree of electron-spin polarization depends greatly on the height and/or position of the δ - doping . Thus, the device can be used as a tunable spin-polarized source by the δ - doping .
