Toward athermal silicon-on-insulator (de)multiplexers in the O-band.

We report on the design, fabrication, and characterization of a 1×4 silicon-on-insulator (SOI) demultiplexer exhibiting a significant reduction of its thermo-optical sensitivity in the O-band. The optical filtering is achieved by cascading several Mach-Zehnder interferometers (MZIs) fabricated on a 300-nm-thick SOI platform. Owing to an asymmetric design of the confinement for each MZIs, we found an athermal criterium that satisfies the spectral requirements. The thermal sensitivity of the structure is analyzed by a semi-analytical model in order to create an athermal multiplexer. Fiber-to-fiber thermo-optical testing reveals a thermal sensitivity of around 17 pm/°C reduced by 75% compared to the standard devices with promising performances for both the crosstalk (15 dB), the insertion losses (4 dB), and absolute lambda registration (<0.25 nm).

Chip-to-chip optical interconnections between stacked self-aligned SOI photonic chips.

Photonic silicon devices are key enabling technologies for next generation High Performance Computers. In this paper, we report the possibility to stack and optically interconnect SOI based photonic chips for future System-In-Package photonic architecture. Combining vertical grating couplers and state-of-the-art flip-chip technology, we demonstrated low loss penalties and wide spectral range optical interconnections between stacked photonic chips.