3D Printed Photoresponsive Materials for Photonics

Polymer photonics explores manufacturing of polymeric materials in order to create devices for light manipulation at the nanoscale. Available lithographic techniques give access to a truly 3D shaping, which can replicate computer-aided designs by several methods. Among them, direct laser writing enables nanoscale precision fabrication. This platform allows integration of advanced materials for reconfigurable elements, whose shape and refractive index can be precisely controlled by external stimuli. This Progress Report collects the recent advances in the field of light-tunable photonics, where polymers are used not only as passive elements for guiding and manipulating light but also to control the optical properties of the devices themselves. This creates dynamic structures with multifunctional performance. Starting from a brief description of light-responsive materials patterned by direct laser writing (focusing on liquid crystalline networks), examples of integration of photonic materials on different platforms are shown—from simple photonic devices (as lenses or diffraction gratings) to their integration in photonic circuits (as active whispering gallery mode resonator coupled to waveguide). As most of the active materials are demonstrated to be biocompatible, implantable photonic platforms can be foreseen for biomedical applications.