| Summary: | Plasmonic metamaterials have been shown to demonstrate a wide array of novel, exploitable optical behaviours across the infrared and visible range of the spectrum. However, to date there has been very little research completed into metamaterials with responses in the ultraviolet region of the electromagnetic spectrum. There are a number of benefits to exploiting the ultraviolet region, including the enhancement of the inherent fluorescence of biological molecules, the ability to selectively photocatalyse chemical reactions and the enormous enhancement factor for UV Raman spectroscopy. In order to produce metamaterials to exploit these benefits, new materials and fabrication processes need to be explored. In this thesis, the development of two different metamaterials that support optical resonances in the ultraviolet region will be shown; the first an array of gallium nanorods and the second an array of aluminium nanoholes. Their fabrication, using a large area self-assembly technique based on anodised aluminium oxide templates, will be explained and a range of optical measurements, including extinction and attenuated total reflection spectroscopy, presented and analysed. These results demonstrate that these metamaterials present strong, geometrically dependent plasmonic resonances in the ultraviolet spectral range. The spectral location of these modes can be finely tuned by controlling the fabrication conditions of the metamaterials. Opportunities for the exploitation of these materials and their future outlook is discussed. In addition to this, the numerical approach underpinning this work is explained and a summary of relevant and supporting work in the literature is presented. The full range of fabrication techniques required to produce these materials is described. The design and construction of the optical spectroscopy system, used to characterise the metamaterials, is fully described and the nature and method of the optical measurements explained. An additional study into controlling the surface roughness of thin aluminium films is also presented.
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