Effect of pressure on the giant magnetoresistance in Co/Cu magnetic multilayers

The effect of pressure and magnetic field on the temperature dependent electrical resistivity ρ(T) of the [Co(1.02nm)/Cu(t _cu nm)] ₂₅ magnetic multilayers (MML) with t _Cu = 0.76 [ferromagnetic (F)] and 1.05 [antiferromagnetic (AF)] has been investigated at low temperature. MR ratio Δρ/ρ _s for t _Cu = 1.05 and 0.76 decreases with increasing pressure. The pressure dependent Δρ/ρ _s for t _Cu = 1.05 is more significant than that for 0.76. ρ(T) at H = 0 and above saturation field H _S (H = 2 T) for Co/Cu MMLs is found to show T ²-dependence in the relatively wide temperature range, 4.2 ≤ T ≤ 20 K, at low temperature. The coefficient of T ² term (= A) for F-state is larger than that for AF-state at ambient pressure. The change of A for t _Cu = 1.05 at H = 0 is smaller than that at H = 2T. These results are discussed on the basis of the electron scattering at interfaces due to magnons or spin-wave.