Percolation threshold and tunneling magnetoresistance in Ag/Ni nanocompacts

The transport and magnetic behaviors of a series of seven two-component (Ag)/sub x/(Ni)/sub 100-x/ nanocompacts , each with a different Ag/Ni mass ratio, are studied with and without the presence of an applied magnetic field. A percolation threshold is found at 30% Ag concentration, higher than which metallic transport is observed. Using the tunneling magnetoresistance mechanism, the magnetorestrictive behaviors of the nanocompacts is investigated. It is observed that the TMR effects become diminshing in low Ni concentration nanocompacts.