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A fully-functional photonic integrated circuit (PIC) platform with supporting active and passive components in the extended short- and mid-wave infrared spectral regime is of significant research interest for next-generation optical systems. Here we design offset quantum well-based photonic integrated circuits which primarily consist of four section-based widely tunable single-mode lasers emitting at 2560 nm. The platform requires the selective removal of InGaAsSb multi-quantum wells located above a GaSb-based optical waveguide layer and then subsequent single blanket GaSb regrowth. Encouraging preliminary experimental results on regrowth are also reported to confirm the feasibility of the proposed PICs. The simulation result for the tunable laser design shows that a tuning range as wide as ~120 nm is possible. The quasi-theoretical work performed here is an initial step towards demonstrating complex non-telecommunication PICs which could offer a comprehensive range of photonic functionalities.
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Automated assembly of hybrid-integrated, chip-scale laser systems
Hybrid photonic integration provides a platform to design and implement novel functionalities unavailable to active or passive material systems alone. We present an automated alignment and assembly process for hybrid-integrated laser systems, comprising silicon nitride (Si3N4) photonic integrated circuits (PICs) edge-coupled to gallium arsenide (GaAs) gain chips (GCs). We design and optimize spot size converters (SSCs) to increase the alignment tolerances between the PICs and GCs. Our automated assembly process has achieved experimental coupling losses of 2.7 dB between the PICs and GCs, closely matching the simulated values. Packaged hybrid lasers, when coupled to a lensed fiber, exhibit slope efficiencies of ∼ 97 mW/A. These results show the feasibility of scaling the production and widespread application of these hybrid laser systems by automating their assembly, which should drive down packaging costs and accelerate research.
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- Award ID(s):
- 2137776
- PAR ID:
- 10584774
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Optics Express
- Volume:
- 33
- Issue:
- 9
- ISSN:
- 1094-4087; OPEXFF
- Format(s):
- Medium: X Size: Article No. 19257
- Size(s):
- Article No. 19257
- Sponsoring Org:
- National Science Foundation
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