A method of fabrication of nanostructured thin film includes depositing a Gd20Fe80 alloy by using the thermal evaporating technique on the top of a high-density nanoporous alumina template. In a particular embodiment, the high-density nanoporous alumina template has a pore diameter of 92 nm and interpore distance of 103 nm and the Gd20Fe80 nanostructured thin film has a layer thickness of 48 nm. The present method results in nanostructured GdFe thin films with large perpendicular magnetic energy density of 4.8 erg/cm2, which is 15 times higher than obtained in the conventional ferromagnetic alloy thin films with PMA.