Structural, electronic and dielectric properties of carbon nanotubes interacting with Co nanoclusters

A new frontier in tuning the electromagnetic response of carbon-based materials, particularly carbon nanotubes, consists in adding metallic clusters or nanoparticles at their external surface. This allows to change optical, dielectric and magnetic properties with potential applications in electronics and telecommunications for aeronautics. By resorting to first principles dynamical simulations, we provide a microscopic picture of the interaction at finite temperature between a carbon nanotube and Co aggregates mimicking the experimental coverage. The electronic structure evolution provides the absorption spectrum and the dielectric function for comparison with experiments and guidelines for tuning these composite systems. [Display omitted] •Advanced computational methods unveil the dielectric response of carbon nanotubes systems in the THz and IR domain.•The mechanism of the interaction between Co nanocluster and carbon nanotubes has been unraveled.•Dynamical behavior of Co nanoclusters on carbon nanotubes at finite temperature leads to aggregation.•absorption spectra and dielectric response are enhanced by Co nanoclusters decorating the nanotube.•A clear link exists between atomic-level features and macroscopic response of the composite system.