Abstract:
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This thesis shows the work done to design, fabricate and characterise the formation of nanostructures built with polystyrene nanospheres (295 nm, 522 nm and 836 nm diameter size) in an attempt to develop all dielectric metamaterials in the optical range. For this purpose, different arrangements were developed to build the nano-devices, using single nanospheres size (295 nm, 522 nm, 836 nm), two nanospheres size (295&522 nm, 295&836 nm, 522&836 nm) and three nanospheres size (295&522&836 nm). The fabrication method uses a electrospray set-up that allows to control de the order of the deposited nanostructures, thus defining and tuning the optical behaviour. Different ordered, semiordered and disordered nanostructures have been successfully fabricated in a very controlled way. Same samples were fabricated by adding isopropyl alcohol in a proportion of 50% polystyrene nanospheres ? 50% isopropyl alcohol. From the different studies, it was proved how the reflectance value is reduced when isopropyl alcohol interacts with polystyrene nanospheres despite the size of the nanospheres. After deposition, optical measurements were performed in order to calculate the percentage of reflectance. Focused Ion Beam (FIB) characterisation verifies the three dimensional distribution of the electrosprayed nanospheres. Simulations were performed in order to compare measured values with theoretical values. The reflectance pattern agrees with the expected results in the cases where total order of the nanostructures (colloidal crystal configuration) is achieved. |