Spin-coherent transport in ferromagnetically contacted carbon nanotubes

摘要: The spin-coherent quantum transport through multiwall carbon nanotubes contacted by ferromagnetic Co pads is investigated experimentally. At 4.2 K, the devices show a remarkable increase of magnetoresistance (MR) ratio with decreasing junction bias, reaching maximum MR 30% at bias current 1 nA. experimental results suggest to be dominated spin-dependent tunneling processes Co/nanotube interfaces and governed local magnetization. We also observe an asymmetry peak position width which attributed exchange biasing in electrode material.