Miniaturized thin-film filters to connect multiple self-written waveguides

Abstract

Self-written waveguides (SWW) have been well investigated within the last decades. In most cases, they are used as low-loss coupling structures, i.e. to connect buried optical structures in photonic integrated circuits. In our work, we extend the field of possible applications for SWWs by embedding a novel thin-film filter to split the beam and connect multiple output ports simultaneously. The multilayer design of the dielectric filter can be customized to enable its application as dichroic beamsplitter for photonic networks. The embedded thin-film filter was characterized in detail and used to connect an additional optical sensing element, which is also based on SWWs, to demonstrate its usability for measurement of physical quantities.