Native fluorescence enhancement using an Aluminum bowtie nano-antenna

Ultraviolet (UV) plasmonic nanostructures hold promises in enabling label-free sensing of biomolecules using their native fluorescence. Several UV plasmonic structures have been explored to enhance native fluorescence of biomolecules, including metallic thin film, particle array, hole array using aluminum, magnesium, indium, etc. However, the enhancement factor of them is quite small, with less than 80 times for nucleic acids and less than 15 times for amino acids. In order to achieve higher enhancement factor, we study a bowtie nano-antenna (BNA) made of aluminum (Al) in the ultraviolet region. The effect of the native oxide layer on Al is also investigated. The numerical simulation has shown 1026x net enhancement with the optimal geometry.