Si photonics uses fine pattern processing technologies for Si integrated circuits (ICs) to realize various micro photonic integration circuits. In Si photonics, Si serves as a photonics platform. In the near future, it will provide a platform for photonics and electronics integration, which will lead to breakthroughs in compact and low-power-consumption communications devices. NTT laboratories, with our accumulated deep knowledge of Si waveguide physics and optical circuit designs, have been developing Si photonics devices for optical communications.
Semiconductor optical modulators are now being used for digital coherent optical fiber communications system. Using the advantages of InP semiconductor material, we have demonstrated a compact InP-based dual-polarization IQ modulator with a small chip size and low drive voltage. In the near future, we aim to realize ultra-high-speed modulators for the next generation of transceivers beyond 100G.