Gain-Integrated 8 × 8 Silicon Photonics Multicast Switch With On-Chip 2 × 4-ch. SOAs

In order to support continuous growth of global IP traffic, highly energy-efficient networks are demanded. One of the key components is an optical multicast switch which has large bandwidth with small power consumption. When using multicast switches, however, intrinsic losses will be an issue especially for large port count switches. Erbium doped fiber amplifiers (EDFAs) are typically used for the loss compensation, although it would much increase the number of components and footprint of the system. One of the options to solve this problem would be an integration technology of semiconductor optical amplifiers (SOAs) on the silicon photonics switches which we have recently developed. In the previous work, we have demonstrated a gain-integrated 4 × 4 silicon matrix switch. For the practical use of our technology, it is very important to show further scalability of the platform. Moreover, it is also important to show applicability to other switch topologies, such as multicast switches. In this article, we demonstrate an 8 × 8 silicon photonics multicast switch with on-chip integrated 2 × 4-ch. SOAs. The on-chip SOAs exhibit a net gain of ~9 dB, which almost compensates for the intrinsic loss. We observe the crosstalk of less than -35 dB. Loss/crosstalk reduction and chip power consumption are also discussed.