Ion beam for synthesis and modification of technostructures

Abstract : The role of energetic ions of energies from a few keV to hundreds of MeV in nanostructuring is highlighted with the examples of nanostructures obtained by ion irradiation experiments at Inter University Accelerator Centre (IUAC), Delhi and Centre de Spectrometrie Nucleaire de Spectrometrie de Mass CSNSM, Orsay. They range from the use of ion or atom beams of a few keV to generate periodic ripples on surface or grow nanocomposite thin films by sputtering to the formations of an isotropic structures under swift heavy ion impacts. Swift ion irradiation of polymers or fullerenes creates strings of carbon particles or wires useful as nanocontacts or field emission tips. The elongation of noble metal particles embedded in insulators attracts attention for the design of light filters or waveguides. The swift heavy ion irradiation of silica film containing Fe nanoparticles, transforms the magnetic easy axis from in-plane to out-of-plane, which is of relevance to the perpendicular magnetic recording of information.