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AbstractThis 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. Graphic Abstract
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High-quality microresonators in the longwave infrared based on native germanium
Abstract The longwave infrared (LWIR) region of the spectrum spans 8 to 14 μm and enables high-performance sensing and imaging for detection, ranging, and monitoring. Chip-scale LWIR photonics has enormous potential for real-time environmental monitoring, explosive detection, and biomedicine. However, realizing technologies such as precision sensors and broadband frequency combs requires ultra low-loss and low-dispersion components, which have so far remained elusive in this regime. Here, we use native germanium to demonstrate the first high-quality microresonators in the LWIR. These microresonators are coupled to partially-suspended Ge waveguides on a separate glass chip, allowing for the first unambiguous measurements of isolated linewidths. At 8 μm, we measured losses of 0.5 dB/cm and intrinsic quality (Q) factors of 2.5 × 105, nearly two orders of magnitude higher than prior LWIR resonators. Our work portends the development of novel sensing and nonlinear photonics in the LWIR regime.
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- PAR ID:
- 10372847
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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