Effect of NiAl underlayer and spacer on magnetoresistance of current-perpendicular-to-plane spin valves using Co2Mn(Ga0.5Sn0.5) Heusler alloy

► CPP spin valves using Co2Mn(Ga0.5Sn0.5) ferromagnetic layers with a new underlayer material. ► NiAl underlayer and spacer improve the thermal tolerance of the spin valve structure. ► NiAl underlayer improves MR ratio compared to Ag because of higher annealing temperature. ► NiAl spacer degrades MR ratios compared to Ag because of short spin diffusion length. ► Potential of heat resistant underlayer and spacer layer for CPP-SV using Heusler alloy.