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The detection of mid-infrared (MIR) light is technologically important for applications such as night vision, imaging, sensing, and thermal metrology. Traditional MIR photodetectors either require cryogenic cooling or have sophisticated device structures involving complex nanofabrication. Here, we conceive spectrally tunable MIR detection by using two-dimensional metal halide perovskites (2D-MHPs) as the critical building block. Leveraging the ultralow cross-plane thermal conductivity and strong temperature-dependent excitonic resonances of 2D-MHPs, we demonstrate ambient-temperature, all-optical detection of MIR light with sensitivity down to 1 nanowatt per square micrometer, using plastic substrates. Through the adoption of membrane-based structures and a photonic enhancement strategy unique to our all-optical detection modality, we further improved the sensitivity to sub–10 picowatt-per-square-micrometer levels. The detection covers the mid-wave infrared regime from 2 to 4.5 micrometers and extends to the long-wave infrared wavelength at 10.6 micrometers, with wavelength-independent sensitivity response. Our work opens a pathway to alternative types of solution-processable, long-wavelength thermal detectors for molecular sensing, environmental monitoring, and thermal imaging.
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Wavelength-scalable mid-infrared photodetectors based on photon-assisted tunneling in MIM metasurfaces
We propose zero-bias, wavelength-scalable, and polarization-selective mid-infrared photodetectors based on metal–insulator–metal (MIM) metasurfaces. Specifically, these photodetectors leverage the second-order quantum conductivity sourced from photon-assisted tunneling and strong electric field localization in the MIM nanojunction to achieve efficient optical rectification. We show that by tailoring metasurface geometry, the incident infrared radiation can be efficiently coupled into the MIM heterojunction, with certain wavelength and polarization selectivity, and the optical rectification effect can be achieved with a photoresponsivity as high as tens of mA/W. Such results may pave a promising route toward the next-generation mid-infrared photodetection and energy harvesting.
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- Award ID(s):
- 2210861
- PAR ID:
- 10660862
- Publisher / Repository:
- Optica Publishing Group
- Date Published:
- Journal Name:
- Journal of the Optical Society of America B
- Volume:
- 42
- Issue:
- 11
- ISSN:
- 0740-3224
- Page Range / eLocation ID:
- 2369
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1364/JOSAB.571626
