Functional metamaterials for lab-on-fiber

Abstract

In this chapter we discuss a versatile method to functionalize the tip of optical fibers for lab-on-fiber applications. At variance with traditional direct writing methods, the photonic functionality is implemented on a flexible, ultrathin support hosting metallic nano-features that is applied on the tip of a fiber. Here we present and discuss several fabrication strategies that combine different substrates with alternative approaches to realize the metallic photonic layer. As a specific application example we focus on a method to filter spectrally the broadband light transmitted through a standard multimode fiber. The filter consists of a metallic nanowire grating on a polymeric substrate, which acts as a guided mode resonance filter with an additional Fano resonance. The advantages and limitations of the presented technique are discussed as well.