MR characteristics of synthetic ferrimagnet based spin-valves with different pinning layer thickness ratios

The dependence of magnetoresistance (MR) ratio and pinning characteristics on the two pinning layer thicknesses, in synthetic ferrimagnetic (SF) struc ture (P2/Ru/P1/AF), was investigated, The pinning field decreased monotonic ally when Deltat (=t(P2) - t(P1)) = 0 while it has its maximum at a specifi c t(P2) when Deltat(=t(P2) - t(P1)) not equal 0 as t(P2) increased. MR rati o reached its maximum at a specific t(P2) as t(P2) increased. In the case o f the fixed t(P2) pinning field decreased whereas MR ratio increased as Del tat increased. This trend is also found when the total thickness of P1 and P2 is fixed so that the current shunting to synthetic ferrimagnet (SF) tril ayer is fixed. Both strong pinning field and sufficient MR ratio could be o btained by selecting appropriate Deltat under the constraint of constant to tal thickness of SF trilayer.