Magnetism and magneto-transport studies in sonochemically prepared amorphous Co_(100-x)Pt_x nano alloys

摘要

Bulk amorphous Co_(100-x)Pt_x (0 ≤ x ≤ 50) nano-alloys have been synthesized using high frequency ultrasound, displaying single domain (4-5 nm) behavior wherein weakly exchange-coupled particles lead to a field-dependent resistivity behavior. Magneto-resistivity is correlated to the order-disorder parameter in these powder compacts. The plot of Δρ/ρ_0 as a function of reduced magnetization indicates that all the systems are weakly exchange coupled.