Production and characterisation of magnetic nanoparticles produced by laser evaporation for ferrofluids

Ferromagnetic metallic nanoparticles were produced by laser evaporation with vapour condensation in an aggregation gas. From iron rich Fe-Si and Fe-Co targets solid alloy particles with α-Fe structure and a mean diameter of 10 nm were obtained. Using a gas pressure of 150 mbar an α-Fe content up to 90 wt% and a saturation magnetisation of 1.4 T were found.