An optically pumped nanophotonic InP/InGaAlAs optical amplifier integrated on a SOI waveguide circuit

A small footprint integrated optical amplifier on Silicon-on-insulator is proposed in this article. By choosing to use optical pumping to drive the device, electrical contacting is avoided and the active waveguide can be made as thin as 100 nm, maximizing the optical confinement in the quantum well layers. Furthermore, the optical pumping is done through the silicon waveguide layer to optimally use the pump light. This leads to a compact device with high gain. We show 8 dB gain in pulsed regime in a 100 μm long device using a peak pump power of only 4.5 mW, while a comparable gain using an electrically pumped device would require an order of magnitude higher power consumption. This is an important step towards a CMOS-compatible optical amplifier for intra-chip optical interconnects.