Al/Al-Oxide/M/Al(M=Fe, Ni)接合の非弾性電子トンネル分光  [in Japanese] Analysis of the Interface in Al/Al-Oxide/M/Al(M=Fe,Ni) Junctions by Inelastic-Electron-Tunneling Spectroscopy  [in Japanese]

Inelastic-electron-tunneling spectroscpy (IETS) was used to investigate the electron states of the interfaces of Al/Al-oxide/Fe(d_<Fe>)/Al and Al/Al-oxide/Ni(d_<Ni>)/Al tunnel junctions. The conductance curves for all junctions showed a minimum around the zero-bias voltage. The IET spectra showed a strong positive peak around 4mV, corresponding to the minimum of conductance curves, while another broad peaks was observed for junctions with d_<Ni>,d_<Fe>≧10Å. The peak positon was differnt from that assigned to the Al-O LO phonon mode observed for Al/Al-oxide/Al junctions. It was confirmed by magnetization measurements that a ferromagnetic layer was formed for films with d_<Ni>≧30Å and d_<Fe>≧10Å. These results were investigated in ralation to the direct and inelastic tunneling process due to magnons.