MR behavior in tunneling junctions with a nonmagnetic metal layer between barrier and electrode

The influence of a nonmagnetic metal (Cu) layer between the barrier and the electrode in ferromagnetic tunneling junctions on magnetoresistance has been investigated. MR decreases with increasing the Cu layer thickness (t/sub Cu/), however, the variations in MR at 77 K with temperature and bias voltage become smaller with increasing t/sub Cu/.