The longwave infrared (LWIR) range, which spans from 6 µm to 14 µm, is appealing for sensing due to strong molecular fingerprints in this range. However, the limited availability of low-loss materials that can provide higher-index waveguiding and lower-index cladding in the LWIR range presents challenges for integrated photonics. In this work, we introduce a low-loss germanium-on-zinc selenide (GOZ) platform that could serve as a versatile platform for nanophotonics in the LWIR. By bonding high-quality thin-film germanium (Ge) to a zinc selenide (ZnSe) substrate, we demonstrate transparency from 2 µm to 14 µm and optical losses of just 1 cm−1at 7.8 µm. Our results demonstrate that hybrid photonic platforms could be invaluable for overcoming the losses of epitaxially grown materials and could enable a wide range of future quantum and nonlinear photonics.
This content will become publicly available on December 1, 2024
This article presents an overview of the current status and future prospects of integrated nonlinear photonics in the long-wave infrared (LWIR) spectrum, spanning 6 to 14 μm. This range is well-suited for applications such as chemical identification, environmental monitoring, surveillance, search and rescue, and night vision. Nevertheless, the advancement of a mature, low-loss chip-level platform for the LWIR remains in its infancy. We examine the materials growth techniques, and fabrication methods associated with integrated nonlinear photonics in the LWIR, highlighting promising platforms like chalcogenide glass, single-crystalline diamond, Ge/SiGe, and III–V compounds. Furthermore, we explore loss mechanisms, dispersion engineering, nonlinear generation of broadband supercontinuum and frequency combs, and device performance, encompassing photodetectors and modulators. Lastly, we propose a roadmap for the future development of integrated nonlinear photonics in the LWIR.
- Award ID(s):
- 2349259
- NSF-PAR ID:
- 10489579
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- MRS Communications
- Volume:
- 13
- Issue:
- 6
- ISSN:
- 2159-6867
- Page Range / eLocation ID:
- 942 to 956
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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