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Van der Waals two-color infrared photodetector
Peisong Wu1,2, Lei Ye3, Lei Tong3
1State Key Laboratory of Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai, 200083, China.
Light, Science & Applications
|January 2, 2022
Summary
Researchers developed a novel, noncooled two-color infrared photodetector for advanced spectral imaging. This breakthrough enables cost-effective, miniaturized infrared detection at near- and mid-infrared wavelengths without cryogenic cooling.
Area of Science:
- Optoelectronics and Photonics
- Infrared Technology
- Materials Science
Background:
- Growing demand for multispectral imaging necessitates cost-effective and miniaturized infrared photodetectors.
- Current limitations include high costs of epitaxial semiconductors and the need for complex cryogenic cooling systems.
- Existing technologies hinder the widespread adoption of infrared multispectral imaging.
Purpose of the Study:
- To demonstrate a noncooled, two-color infrared photodetector capable of simultaneous near-infrared (NIR) and mid-wavelength infrared (MWIR) detection.
- To overcome the limitations of current infrared photodetector technologies, focusing on cost and operational temperature.
- To enable temporal-spatial coexisting spectral blackbody detection.
Main Methods:
- Fabrication of a two-color infrared photodetector utilizing vertically stacked back-to-back diode structures.
- Implementation of an intermediate layer functioning as an electron-collecting layer and hole-blocking barrier to control the built-in electric field.
- Characterization of photodetector performance, including signal separation, crosstalk, and specific detectivity (D*).
Main Results:
- Demonstration of a noncooled, two-color infrared photodetector operating at both NIR and MWIR wavelengths.
- Achieved ultralow crosstalk of approximately 0.05% through precise control of the intermediate layer.
- Verified performance with a specific detectivity (D*) of 6.4 × 10^9 cm Hz^1/2 W^-1 at 3.5 μm and room temperature.
- Successful NIR/MWIR two-color infrared imaging and absolute temperature detection.
Conclusions:
- The developed two-color infrared photodetector offers a promising, cost-effective solution for advanced spectral imaging applications.
- The device's noncooled operation and miniaturization potential facilitate integration into various platforms.
- This technology paves the way for enhanced infrared detection and temperature sensing without complex cooling systems.
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