Spin-polarized electron injection in Co/Cu/Fe sandwich structure

A material asymmetry Co/Cu/Fe junction structure has been prepared for stud ying the spin-polarized electron injection at 77 K. The sample performance was demonstrated to be analogous to that of a bipolar transistor. The maxim al value of the output pulse voltage between Cu and Fe layers could reach t he order of several mu V when the bias current between Co and Cu layers was 10 mu A. The interface roughness, photograph of material, magnetic loop an d injection characteristic curves have been measured. Some important points on this topic have been discussed.