Bloch surface waves-controlled emission of organic dyes grafted on a one-dimensional photonic crystal

Abstract

An alternative route to plasmon-controlled fluorescence for improving the detection of fluorescence is proposed. In place of a metallic layer, a suitable silicon-based one-dimensional photonic crystal is used to generate a Bloch surface waves-coupled emission from a thin polymeric layer decorated with a fluorescent dye. Fluorescent radiation coupled to Bloch surface waves is strongly polarized and directional, with an angular divergence of 0.3° corresponding to a spectral bandwidth of 3 nm. Within this range, an overall signal enhancement of a factor larger than 500 is obtained as compared to a conventional glass substrate thanks to an additional enhancement mechanism based on dyes excitation via Bloch surface waves.