Multi-lane, high-power Photonic Integrated Circuit-based Erbium-Doped Amplifier

Project Information

MAGNIFY

Grant agreement ID: 101113302

DOI

10.3030/101113302

Project closed

EC signature date 13 May 2023

Start date 1 June 2023

End date 31 May 2026

Funded under

• The European Innovation Council (EIC)

Total cost

€ 1 584 066,25

EU contribution

€ 1 584 066,25

Coordinated by

LIGENTEC FRANCE
France

Periodic Reporting for period 1 - MAGNIFY (Multi-lane, high-power Photonic Integrated Circuit-based Erbium-Doped Amplifier)

Reporting period: 2023-06-01 to 2024-05-31

Summary of the context and overall objectives of the project

The ability to achieve rare-earth gain in integrated photonic circuits has the potential to transform integrated photonics; it could enable wideband gain covering the entire telecommunication channels, allow for very low noise amplification, and enable simultaneous amplification of multiple channels –a long-standing challenge in itself. However, the much lower gain coefficient of rare-earth ions compared to III-V semiconductors requires the development of photonic circuits with ultra-low optical losses and long waveguides to achieve practical output powers.

Recently, using an ultralow-loss silicon nitride (Si3N4) photonic integrated circuit up to 0.5 meters in length, and using ion implantation of Erbium, it has been possible to build an optical Erbium amplifier on a photonic device, providing 30 dB net gain in the optical communication C-band, and an output power of >140 mW on chip. This performance is on par with state-of-the-art commercial , high-end EDFAs.

The objective of the MAGNIFY project is to transition photonic integrated circuit-based Erbium-doped waveguide amplifiers (EDWA) from a laboratory prototype to a demonstrator, which will be used for early access demonstrator studies with telecommunication companies and enable iterative feedback. In addition to technology maturation – which will be carried out in the areas of coherent communications and microwave photonics – the aim is to develop the basis for commercialization.

EDWAs address the emerging bottleneck of compact, high-power, and cost-effective solutions for applications in mega-datacenters and deep-sea optical links, where space constraints severely limit the scaling of more fiber channels. The range of applications where EDWA can be used includes traditional areas where EDFAs are deployed as well as emerging new application domains. The domains where EDWA can be used as the amplifier of choice include line cards for data center infrastructure, radio frequency over fiber for 5/6G networks, free-space satellite communications, deep sea amplifiers for optical repeaters, coherent LiDAR.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The overall progress of the MAGNIFY project is in line with the defined objectives. Key progress includes the proof-of-concept demonstration of single and multi-lane EDWAs with experimental measurements and the development of the AN200 silicon nitride process by LGTF. We have submitted circuit layout designs to LGTF for fabrication by a commercial foundry. We have made significant efforts to disseminate the project goals and current results at tradeshows and leading conferences in optics and photonics.

LGTF has received the design files including the mask design from EPFL. The design has been generated according to the design manual and the first tape-out is in progress. The AN200 process is ready to fabricate Si3N4 wafers; there will be different wafer splits, including air-cladded Si3N4 and wafers with Si3N4 and top oxide, whose thickness will be finalized based on EPFL’s feedback from the first split.

Prototype development included preparation and submission of the wafer design layout to LGTF and simulation of components such as WDM couplers, input couplers, and spiral waveguide dimensions. EPFL fabricated Si3N4 wafers with a waveguide thickness of 200 nm, performed an Er doping concentration optimization process with different ion implantation providers, measured passive losses and successfully measured off-chip net gain of up to 17 dB in EDWA chips using a 1480 nm pump. EPFL performed in-house packaging in butterfly modules of single-lane hybrid integrated EDWAs and measured off-chip net gain in excess of 15 dB.

In addition, a first draft of proof-of-concept experiments for coherent communications and microwave photonics applications was developed.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

We demonstrated more than 100 mW of amplified signal on chip, which is the first demonstration of its kind in integrated photonics. For the first time, we carried out photonic packaging of the first prototypes of EDWA. This allows us to build samples for early adopters of the technology and to start proof-of-concept experiments with external partners.

PFL’s image of a fiber coupled photonic integrated circuit (PIC) in a custom package.