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Infrared Degenerate Four-wave Mixing with Upconversion Detection for Quantitative Gas Sensing
Published on: March 22, 2019
Shortwave Infrared Upconversion Imaging with Tunable Dual-Resonance Microcavity
Kangning Yu1,2, Dileep Kottilil2, Liangliang Liang3
1Department of Chemistry, National University of Singapore, Singapore 117543, Singapore.
Nano Letters
|May 25, 2026
Summary
We developed a cost-effective shortwave infrared (SWIR) imaging method using silicon cameras and photon upconversion nanoparticles. This approach offers high resolution at a lower cost than traditional InGaAs cameras.
Area of Science:
- Optics and Photonics
- Materials Science
- Nanotechnology
Background:
- Shortwave infrared (SWIR) imaging is crucial for applications like night vision and industrial inspection.
- Current InGaAs-based SWIR cameras are limited by high costs due to complex fabrication and cooling needs.
Purpose of the Study:
- To develop a cost-effective SWIR imaging solution using standard silicon cameras.
- To enhance upconversion efficiency for improved SWIR imaging performance.
Main Methods:
- Utilized NaYF4:Er@NaYF4 core-shell nanoparticles for photon upconversion.
- Integrated nanoparticles within a tunable, dual-resonance Fabry-Pérot cavity.
- Employed a standard silicon camera for detection.
Main Results:
- Achieved up to 10^4-fold increase in upconversion intensity.
- Enabled SWIR imaging at 1550 nm with sub-10 μm spatial resolution.
- Demonstrated spectral tunability via spatially varying cavity length.
Conclusions:
- The developed platform offers a scalable and cost-effective alternative to InGaAs-based SWIR imaging.
- This technology leverages mature silicon technologies and cavity-enhanced photon upconversion.
- Potential applications include silicon wafer alignment and low-visibility imaging.
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