The migration behavior of cadmium (Cd) implanted into glassy carbon and the effects of annealing on radiation damage introduced by ion implantation were investigated. The glassy carbon substrates were implanted with Cd at a dose of 2×10 16 ions/cm 2 and energy of 360 keV. The implantation was performed at room temperature (RT), 430 °C and 600 °C. The RT implanted samples were isochronally annealed in vacuum at 350, 500 and 600 °C for 1 hour and isothermally annealed at 350 °C up to 4 hours. The as-implanted and annealed samples were characterized by Raman spectroscopy and Rutherford backscattering spectrometry (RBS). Raman results revealed that implantation at room temperature amorphized the glassy carbon structure while high temperature implantations resulted in slightly less radiation damage. Isochronal annealing of the RT implanted samples resulted in some recrystallization as a function of increasing temperature. The original glassy carbon structure was not achieved at the highest annealing temperature of 600 °C. Diffusion of Cd in glassy carbon was already taking place during implantation at 430 °C. This diffusion of Cd was accompanied by significant loss from the surface during implantation at 600 °C. Isochronal annealing of the room temperature implanted samples at 350 °C for 1 hour caused Cd to diffuse towards the bulk while isothermal annealing at 500 and 600 °C resulted in the migration of implanted Cd toward the surface accompanied by a loss of Cd from the surface. Isothermal annealing at 350 °C for 1 hour caused Cd to diffuse towards the bulk while for annealing time > 1 hour Cd diffused towards the surface. These results were interpreted in terms of trapping and de-trapping of implanted Cd by radiation damage.

Plasmonic based hybrid noble metal nanoclusters (NCs) have gained much interest in various technological applications such as optoelectronics, photonic devices and nonlinear media including biomedical applications due to their tunable optical properties. Here, Ag NCs are grown as embedded in glass using simple ion-exchange process and effect of various parameter including post thermal treatment is studied on tunability of their optical behavior (plasmonic, optical nonlinearity, and photoluminescence properties) in view of their potential applications in nanophotonics devices and as nonlinear media. The tunable optical, structural and thermodynamic properties associated with the rapid growth and agglomeration of Ag NCs in the glass is also studied under the post thermal treatment process. The various techniques such as XRD, RBS, Z-scan and UV-vis, XPS, PL and TEM are used for characterizing ion exchanged samples. A blue shift of 15 nm is observed significantly in optical absorbance as a function of post thermal treatment. Open and closed aperture Z-scan experiments show strong nonlinear absorption coefficients for the Ag NCs. The thermodynamic parameters such as enthalpy (ΔH), entropy (ΔS) and Gibbs energy (ΔG) for the nucleation and growth of the Ag NCs in the glass matrix are calculated at different temperatures with an activation energy of 59 kJ mol À1 obtained by the Arrhenius linear equation and a model is suggested. In addition, these Ag NCs embedded glasses exhibit good antimicrobial activities (against E. coli bacteria) with a change in antibacterial behavior at higher annealing temperature indicating their multifunctional applications. status solidi physica a Surface Plasmon Resonance www.pss-a.com

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The effect of swift heavy ion (Xe 167 MeV) irradiation on polycrystalline SiC individually implanted with 360 keV Kr and Xe ions at room temperature to fluences of 2×10 16 cm -2 and 1×10 16 cm -2 respectively, was investigated using transmission electron microscopy (TEM), Raman spectroscopy and Rutherford backscattering spectrometry (RBS). Implanted specimens were each irradiated with 167 MeV Xe +26 ions to a fluence of 8.3×10 14 cm -2 at room temperature. It was observed that implantation of 360 keV Kr and Xe ions individually at room temperature amorphized the SiC from the surface up to a depth of 186 and 219 nm respectively. Swift heavy ion (SHI) irradiation reduced the amorphous layer by about 27 nm and 30 nm for the Kr and Xe samples respectively. Interestingly, the reduction in the amorphous layer was accompanied by the appearance of randomly oriented nanocrystals in the former amorphous layers after SHI irradiation in both samples. Previously, no similar nanocrystals were observed after SHI irradiations at electron stopping powers of 33 keV/nm and 20 keV/nm to fluences below 10 14 cm -2 . Therefore, our results suggest a fluence 2 threshold for the formation of nanocrystals in the initial amorphous SiC after SHI irradiation.Raman results also indicated some annealing of radiation damage after swift heavy ion irradiation and the subsequent formation of small SiC crystals in the amorphous layers. No diffusion of implanted Kr and Xe was observed after swift heavy ion irradiation.