Market Perspectives of O-band GaAs QD Devices at the ECOC 2024
As is customary during ECOC, the 2024 event held at Frankfurt Messe featured the ‘Market Focus’ session, where industry leaders shared their insights on emerging trends while showcasing cutting-edge products and solutions within the optical communication sector.
Innolume was honored to be invited to present at this prestigious event. Dr. Alexey Kovsh delivered a presentation titled “Market Perspectives of O-band GaAs QD Devices.”
Key Highlights from the Presentation:
1. The Advancement of Quantum Dot Lasers:
The presentation highlighted the significant progress of quantum dot (QD) lasers from theoretical concepts to industrial deployment. One of the reasons for the extended timeline is that QDs are relatively slow for direct modulation. Innolume had been awaiting the maturation of external modulation technologies, such as Silicon Photonics, to unlock the full potential of QD lasers.
2. Key Benefits for Optical Transceiver Manufacturers Using Silicon Photonics or Other Modulation Technologies:
- Record Power Conversion Efficiency at High Temperatures: QD lasers deliver high power conversion efficiency even under elevated temperatures, like 20% at 100°C.
- Reduced Sensitivity to Back Reflection: QD lasers demonstrate approximately 15 dB more resistance to back reflection compared to conventional CW DFB lasers based on InP Quantum Wells. This feature is particularly beneficial for passive on-wafer packaging of laser diodes to Silicon Photonics PICs, allowing laser placement without the need for an optical isolator.
- Simultaneous Wavelength Generation and Amplification: The presentation also emphasized the ability of QD lasers to simultaneously generate (as a comb-laser) and amplify (as WDM SOA) multiple wavelengths, a key technology for future high-bandwidth DWDM optical interconnect systems.
- Narrow Lasing Line: An important characteristic for applications like FMCW LiDARs and coherent communications in the O-band.
- Reliability: Dr. Kovsh emphasized that, to date, there has been no reported case of sudden device failure in the history of QD laser use.
3. First Semiconductor Equivalent of EDFA – QD SOA:
The presentation also introduced the QD Semiconductor Optical Amplifier (SOA), a breakthrough equivalent to traditional EDFA, but in a fully semiconductor-based device:
- WDM Data Transmission: This device enhances WDM data transmission systems, improving power budgets by up to 15 dB.
- High Power Output: Capable of delivering over 1W at 85°C from a narrow single-mode chip (without tapered design), with excellent beam quality, making it ideal for O-band FMCW LiDARs and terrestrial free-space optical communication.
4. Economic Outlook for GaAs Production:
Dr. Kovsh also covered the economic aspects of GaAs production, a key material in LEDs, RF devices, and laser diodes. In 2023, consumption of 6-inch GaAs wafers reached 3 million units, reflecting strong demand. The manufacturing process, supported by MBE 6000-type systems, allows production of wafers of varying sizes.
5. Reliability of Quantum Dot Lasers:
One of the most unique features of QD lasers is their exceptional reliability. Ongoing studies suggest that QD lasers can have a lifespan exceeding 10 years at 85°C and a power level of 200mW. A particularly notable advantage is that these lasers may not require a burn-in test. Throughout Innolume’s history of shipping tens of thousands of QD lasers, there has not been a single case of sudden device failure.
