Lao, Y-F, Perera, AGU, Li, LH orcid.org/0000-0003-4998-7259 et al. (3 more authors) (2014) Tunable hot-carrier photodetection beyond the bandgap spectral limit. Nature Photonics, 8 (5). pp. 412-418. ISSN 1749-4885
Abstract
The spectral response of common optoelectronic photodetectors is restricted by a cutoff wavelength limit λ that is related to the activation energy (or bandgap) of the semiconductor structure (or material) (Δ) through the relationship λ = hc/Δ. This spectral rule dominates device design and intrinsically limits the long-wavelength response of a semiconductor photodetector. Here, we report a new, long-wavelength photodetection principle based on a hot-cold hole energy transfer mechanism that overcomes this spectral limit. Hot carriers injected into a semiconductor structure interact with cold carriers and excite them to higher energy states. This enables a very long-wavelength infrared response. In our experiments, we observe a response up to 55 μm, which is tunable by varying the degree of hot-hole injection, for a GaAs/AlGaAs sample with Δ = 0.32 eV (equivalent to 3.9 μm in wavelength).
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | (c) 2014 Macmillan Publishers Limited. All rights reserved. This is an author produced version of a paper published in Nature Photonics. Uploaded in accordance with the publisher's self-archiving policy |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Electronic & Electrical Engineering (Leeds) > Pollard Institute (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 22 May 2014 13:04 |
Last Modified: | 14 Feb 2019 12:24 |
Published Version: | http://dx.doi.org/10.1038/nphoton.2014.80 |
Status: | Published |
Publisher: | Nature Publishing Group |
Identification Number: | 10.1038/nphoton.2014.80 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:78934 |