Spin-dependent tunneling has been investigated for nanostructured ferromagnetic tunnel junctions, in which an insulating nanostructured film made of layered hard ferromagnetic Co80Pt20 nanoparticles dispersed in an insulating SiO2 matrix is sandwiched between two soft ferromagnetic electrodes, an Fe/Co80Pt20 as a bottom electrode and a Co9Fe as a top electrode. The junctions investigated have three tunnel barriers and exhibited tunnel magnetoresistance of 9% at room temperature with a small resistance at a low field. The charging energy of the particles with an average diameter of 7 nm was estimated to be 45 meV from the temperature dependence of the resistance. Coulomb blockade was not observed for the junctions because of the low junction resistance.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)