Light coupling in polymer nanofibers: From single-photon emission to random lasing

The understanding of the phenomena underlying the interaction of photons with dielectric, metallic and hybrid microand nano-structures and the development of advanced fabrication tools have paved the way to the realization of complex, nanostructured photonic structures, with tailored and exotic absorption and emission properties. Among such nanostructured materials, polymer nanofibers have intriguing and specific properties: they can embed molecular and quantum dot light sources, they can transport light among distant emitters and they can be arranged in 2-dimensional and 3-dimensional architectures in a controlled fashion, forming complex networks of interacting light emitters. However, coupling of light with polymer nanofibers depends on many variables, being often limited by the arrangement and positioning of the nanoscale light-sources, and by the fiber geometry. Here we report on the fabrication of active polymer nanofibers with improved surface properties and controlled geometry by electrospinning. Polarization and momentum spectroscopy of light emitted by molecular compounds and single quantum dots embedded in electrospun polymer fibers, evidence that efficient, nanostructured photon sources with targeted polarization and coupling efficiency can be realized in nanofiber-based photonic environments.