Paul van Gerven
10 September 2020

Researchers at the University of Twente have developed a light amplifier that can be integrated on an optical chip. In photonics, this component is typically bulky and needs to be connected separately to the system, which introduces losses and vulnerabilities. The amplifier developed by Sonia García Blanco’s group is small enough to integrate on a chip, yet doesn’t compromise on amplification performance. Gracía Blanco received an ERC Proof of Concept grant to accelerate market readiness of the research concept.

Optical amplifier
Credit: University of Twente

In fiber-optic systems, light is often amplified using the rare earth element erbium. To make a much smaller version of this system, the Twente researchers designed a special waveguide architecture made of erbium-doped aluminum oxide. The big question was: how to connect this component to the rest of the circuit?

This was achieved by using a double photonic layer coupler technology developed in García Blanco’s group. A special ‘tapering’ design permits transferring the light back and forth between the passive silicon nitride photonic circuit and the amplifier section, with negligible loss. In this way, the amplifier section becomes a building block that can be introduced by chip designers into any photonic chip that requires amplification.