On-chip optical sources of 3D photonic integration based on active fluorescent polymer waveguide microdisks for light display application

Abstract

In this work, on-chip three-dimensional (3D) photonic integrated optical sources based on active fluorescent polymer waveguide microdisks are proposed for light display application. Fluorescent green and red oligomers with high-efficiency photoluminescence are doped into epoxy crosslinking SU-8 polymer as the waveguide gain medium. The microdisk-based on-chip optically pumping light sources are designed and fabricated using the organic functionalized materials by direct UV written process. The promising stacking dual-microdisk structures with double gain layers could provide white signal light source generated perpendicular to the chip, and green signal light source stimulated in the chip. The approach could realize the monolithically on-chip assembled vertical and horizontal bright emitters. The optical pumping threshold power is obtained as 50 mW with continuous-wave (CW) pumping. The average gain coefficient of a white light source is measured by vertical fiber coupling as 112 dB/W, and that of green light source by horizontal fiber coupling as 137 dB/W, respectively. The rising and falling response time of the on-chip optical sources are 60 and 80 µs under modulating pulsed pumping. This technique is very promising for achieving 3D integrated light display application, including photonic circuits and optical information encryption.