Extended wavelength infrared photodetectors
| Autor: | Lianhe Li, Suraj P. Khanna, Li Chen, A. G. Unil Perera, Edmund H. Linfield, Dilip Chauhan |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
Physics
Band gap business.industry Phonon Infrared Detector General Engineering Photodetector Heterojunction 02 engineering and technology 021001 nanoscience & nanotechnology Atomic and Molecular Physics and Optics Wavelength 020210 optoelectronics & photonics Optics 0202 electrical engineering electronic engineering information engineering Optoelectronics Infrared detector 0210 nano-technology business |
| ISSN: | 0091-3286 |
| Popis: | Extension of the wavelength threshold of an infrared detector beyond λt=hc/Δ is demonstrated, without reducing the minimum energy gap (Δ) of the material. Specifically, a photodetector designed with Δ=0.40 eV, and a corresponding λt=3.1 μm, was shown to have an extended threshold of ∼45 μm at 5.3 K, at zero bias. Under negative and positive applied bias, this range was further extended to ∼60 and ∼68 μm, respectively, with the photoresponse becoming stronger at increased biases, but the spectral threshold remained relatively constant. The observed wavelength extension arises from an offset between the two potential barriers in the device. Without the offset, another detector with Δ=0.30 eV showed a photoresponse with the expected wavelength threshold of ∼4 μm. |
| Databáze: | OpenAIRE |
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