Permittivity and permeability of Fe(Tb) nanoparticles and their microwave absorption in the 2-18 GHz range

摘要

The permittivity and permeability of the Tb-doped and undoped Fe core-shell nanoparticles were investigated for frequencies from 2 to 18 GHz. The particles were synthesized by arc discharge and contain some oxygen, probably in the form of Fe_2O_3, Fe_3O_4, and Tb_2O_3, whereas the core material is Fe. Both the electromagnetic materials constants and the morphology of the Fe nanoparticles are changed by Tb addition, which gives rise to the shifts to higher frequencies and thinner thicknesses of the maximum microwave absorption in the Tb-doped Fe nanoparticles.