Curie temperature enhancement in Fe/sub 3/C nanoparticles made by laser pyrolysis

We report on the magnetic properties of passivated and unpassivated ferromagnetic Fe/sub 3/C nanoparticles made by laser pyrolysis. The particles have a Curie temperature well above that measured for the bulk material, and a room temperature coercive force of approximately 600 Oe. The nanoparticles offer the possibility of high temperature magnets, sensors, or materials for temperature dependent EMI shielding.