Design and fabrication of 3D-printed Y-branch power splitters based on the conjugated polymer PFeF8
Conjugated polymers are essential materials employed in organic optoelectronics. Their application in photonic circuits is a subject of increasing relevance and study. In this work, we present the design, numerical simulation, fabrication, and experimental characterization of a Y-branch optical power splitter based on the PFeF8 conjugated polymer, a basic building block used in such circuits. The blend with PMMA enables the control and reduction of the refractive index and offers a large transparency region above 550 nm, which is useful for the design of waveguide structures based on materials with a low extinction coefficient. Measurements in samples of the PFeF8/PMMA blend at concentrations of 5% and 10% revealed propagation losses of 0.022 dB/mm (R2 = 0.96) and 0.025 dB/mm (R2 = 0.90), respectively. The splitters fabricated with the DLP 3D printing technique show excess loss from 4.78 dB to 6.36 dB, most of it due to scattering on the guiding structure. An average 0.16 dB power imbalance between the two arms indicates the uniformity of the splitting ratio.