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X‐ray emission spectroscopy with high‐energy resolution was used for characterizing differences in the valence band of carbon films deposited by ion implantation in various conditions of bombardment and with various substrates, with respect to crystalline diamond and other diamondlike coatings. The obtained results were compared with calculations of the partial density of 2p states in defected diamond, and the nature of point defects in the implanted films could be identified. In addition, x‐ray emission spectra of substrate atoms indicated a chemical interaction at some interfaces.

The photoluminescence properties of as-deposited and 90 MeV Si ion irradiated fullerene films are reported. The irradiation of fullerene films leads to some enhancement or quenching in molecular transition intensities (photoluminescence intensities) depending on the ion fluence. These effects are explained in terms of lowering in the energy level symmetry resulting from induced chemical disordering. The structural modifications occurring upon irradiation were investigated using Fourier transform infrared and UV-vis spectroscopies.

This article reports on the formation and electronic characteristics of conducting carbon nanowires produced by swift heavy ion irradiation of a fullerene thin film. This study shows that it is possible to create arrays of carbon nanowires, which are perfectly parallel to each other and perpendicular to the substrate. As-deposited fullerene films exhibit poor field emission characteristics with breakdown fields as high as 51 V/mu m, whereas low dose ion irradiated fullerene film produces a threshold field as low as 9 V/mu m. The present approach of making conducting carbon nanowires by ion irradiation for potential field emitters and large area applications is also discussed.

The present work reports the synthesis of elongated Au nanoparticles (NPs) parallel to each other, embedded in silica matrix. Au NPs in silica, prepared using rf magnetron sputtering, were irradiated by 120MeV Au ions at different fluences to induce elongation. Optical absorption study of irradiated film showed a clear splitting of surface plasmon bands corresponding to transverse and longitudinal modes. Transmission electron microscopy investigations of pristine and irradiated samples revealed an elongation (aspect ratio of ∼3.5) in Au NPs occurred as a result of irradiation. The results are discussed in the framework of thermal spike model.

Thin silica films containing Au nanoparticles were prepared by cosputtering. The kinetics of the growth of nanoparticles under 90 MeV Ni ion irradiation was studied by in situ x-ray diffraction. The growth of nanoparticles from 4 (for pristine) to 9 nm at a fluence of 1×1014 ions/cm2 was observed, in accordance with the observations made by transmission electron microscopy analyses. The present study shows that the ion irradiation is an effective tool for tailoring the size of nanoparticles. The results are discussed in the framework of thermal spike model.

Conducting nanowires parallel to each other, embedded in fullerene matrix are synthesized by high energy heavy ion irradiation of thin fullerene film at low fluence (up to 5×1011ions∕cm2). The conductivity of the conducting zone is about seven orders of magnitude higher than that of the fullerene matrix. The conducting nanowires are evidenced by conducting atomic force microscopy. The typical diameter of the conducting tracks is observed to be about 40–100nm. The creation of conducting wires is explained by transformation of fullerene to conducting form of carbon in the ion track, surrounded by the polymerized zone. The polymerization of fullerene is evidenced by Fourier transform infrared spectroscopy.