Optical fibre nanowire sensors and applications

Abstract

Optical fibre nanowires (OFN) have recently attracted increased attention because of their numerous applications in sensing and particle manipulation [1] and their extraordinary optical and mechanical properties, which include, amongst others:biocompatibility: OFNs show good compatibility with cells/ biological matter as they are made from silica.configurability/flexibility: OFN are manufactured stretching optical fibres, thus they maintain their original size at the extremities (fig. 1), allowing for prompt connection to any fiberised source/detector. robustness: OFNs are extremely strong and have a conventional fibre pigtail at their extremity, thus can be handled with tools typical of the macroscopic world.large evanescent fields: a considerable fraction of the transmitted power can propagate outside the OFN physical boundary when the OFN size is small, allowing for enhanced sensing and optical manipulation. strong confinement: when OFNs are nanostructured and metal coated, light can be confined to 50-100 nm spot sizes, allowing for nanosensing and single nanoparticle trapping/manipulation