@article{GoldenbergKoehlerDreyer2021, author = {Goldenberg, Leonid and K{\"o}hler, Mathias and Dreyer, Christian}, title = {SiO2 Nanoparticles-Acrylate Formulations for Core and Cladding in Planar Optical Waveguides}, series = {Nanomaterials}, volume = {11}, journal = {Nanomaterials}, number = {5}, publisher = {MDPI}, issn = {2079-4991}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-14057}, year = {2021}, abstract = {A combination of acrylate formulations and SiO2 nanoparticles is investigated with the aim to improve the optical properties of low-refractive index polymers that are used for the fabrication of planar optical waveguides. A decrease in refractive index and also in the thermo-optic coefficient of nanocomposite materials is clearly demonstrated, while some formulations exhibit an increase in the glass transition temperature. The possibility of using these nanocomposite materials to fabricate waveguiding layers with low optical propagation losses at telecommunication wavelengths around 1550 nm is also shown. The nanomaterials can be applied in optical microchips on polymer platforms.}, language = {en} } @article{GoldenbergKoehlerKahleetal.2020, author = {Goldenberg, Leonid and K{\"o}hler, Mathias and Kahle, Olaf and Dreyer, Christian}, title = {Impact of inorganic nanoparticles on optical properties of low refractive index waveguiding polymers}, series = {Optical Materials Express}, volume = {10}, journal = {Optical Materials Express}, number = {11}, issn = {2159-3930}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-13521}, pages = {2987 -- 2997}, year = {2020}, abstract = {The objective of this work is to improve the optical properties of low refractive index polymers used for waveguide by introduction of inorganic nanoparticles. Copolymers of fluorinated monomers and glycidyl methacrylate are used. Introduction of SiO2 nanoparticles into polymer matrix is performed by direct mixing; copolymerization with SiO2 nanoparticles modified by monomer, and in situ sol-gel formation of SiO2 during photochemical cross-linking and annealing catalyzed by photoacid generator. It is demonstrated that nanoparticles are able to decrease thermo-optic coefficient. It is also possible to fabricate waveguiding layers by direct introduction of nanoparticles without compromising of optical propagation losses.}, language = {en} } @article{GoldenbergKoehlerDreyer2025, author = {Goldenberg, Leonid and K{\"o}hler, Mathias and Dreyer, Christian}, title = {Fluorinated Polymers for Photonics—From Optical Waveguides to Polymer-Clad Glass Optical Fibers}, series = {Applied Sciences}, volume = {15}, journal = {Applied Sciences}, number = {4}, publisher = {MDPI}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:526-opus4-19967}, year = {2025}, abstract = {In this paper, our work in the field of fluorinated UV-curable polymers is reviewed. These polymers possessing tunable low refractive indices and low optical propagation losses for telecommunication wavelengths are intended to be used as core and cladding materials for the fabrication of passive channel waveguides in optical microchips on the polymer platform. This application requires low thermo-optic coefficients. With this goal, we used a combination of fluorinated polymers with low-refractive index inorganic nanoparticles of SiO2 and MgF2. Another application requiring extremely low refractive indices is polymer cladding for optical glass fibers. UV-curable fluorinated monomers/oligomers were used.}, language = {en} }