Abstract
Cobalt nanoparticles have been fabricated by laser ablation of metal target at laser wavelengths of 1064 nm and 532 nm. The target was immersed in water during the ablation. Size of the resulted nanoparticles was determined by optical microscope and field emission scanning electron microscope (FESEM). It was observed that the minimum particle was 6 nm in diameter. Ultraviolet to visible (UV-vis) spectra and photoluminescence (PL) spectra were applied to characterize the optical properties of these products. In order to investigate the magnetic properties, the particles were spread on clean substrates for vibrating sample magnetometer (VSM) measurement. It was fond that magnetic properties of generated cobalt nanoparticles were obviously influenced by their sizes. Effects for the different laser wavelengths on particle formation were compared.