Activity: Talks and presentations › Conference presentations
Para-hexaphenylene (p6P) molecules can self-assemble via vapour deposition onto a muscovite mica substrate to form crystalline either straight nanofibers with length of hundreds of micrometers or nanofiber rings with diameters of a few micrometers. Such p6P nanofibers have peculiar optoelectronic properties such as a blue, polarized photoluminescence output upon UV excitation and the ability to act as optical waveguides and random lasers. Waveguiding p6P rings would be of particular interest as they could be used in ring resonators as components in compact integrated photonic circuits. Compared to straight nanofiber growth, the formation of nanofiber rings requires an additional treatment of the mica substrate with water prior to deposition of the molecules. Here we demonstrate the formation of microrings with diameters larger than 10 µm. We find that the waveguided light through a nanofiber microring shows damping very similar to straight waveguides. The spatially resolved spectra of the guided light through straight and curved sections (more than 90 ° bend) of a nanofiber show significant damping in the blue range of the spectrum due to reabsorption, while only very small losses are observed at below-gap photon energies. Current efforts focus on the spectral behaviour of the microrings.