Optimizing nano-mirror coupler design for high-efficiency optical interconnects (Conference Presentation)

Integrated circuits have revolutionized a variety of technical disciplines; however, traditional silicon-based circuits have inherent functionality and performance constraints. Photonic 3D Heterogeneous Integration (p-3DHI) is a pioneering approach that combines photonic and electrical components in a vertically stacked design. This method leverages diverse materials and advanced fabrication techniques, including femtosecond laser writing and hybrid bonding, to enhance integration density and performance. The grating coupler, which connects Si-PICs with glass substrates and provides a great deal of structural flexibility, is a key component of this system. Cutting-edge grating couplers for Si-PICs and glass waveguides have better coupling efficiency than edge couplers (<1 dB/facet), but they have a higher insertion loss (>3 dB/facet). Our work is focused on optimizing the grating structure between Si-PICs and glass waveguides in order to realize an efficient grating coupler with less than 1.1 dB of insertion loss. This could lead to improvements in speed, energy efficiency, and scalability for applications such as optical communications, quantum optics, and sensing.