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III–V semiconductor type-II superlattices (T2SLs) are a promising material system with the potential to significantly reduce the dark current of, and thus realize high-performance in, infrared photodetectors at elevated temperatures. However, T2SLs have struggled to meet the performance metrics set by the long-standing infrared detector material of choice, HgCdTe. Recently, epitaxial plasmonic detector architectures have demonstrated T2SL detector performance comparable to HgCdTe in the 77–195 K temperature range. Here, we demonstrate a high operating temperature plasmonic T2SL detector architecture with high-performance operation at temperatures accessible with two-stage thermoelectric coolers. Specifically, we demonstrate long-wave infrared plasmonic detectors operating at temperatures as high as 230 K while maintaining dark currents below the “Rule 07” heuristic. At a detector operating temperature of 230 K, we realize 22.8% external quantum efficiency in a detector absorber only 372 nm thick ([Formula: see text]) with a peak specific detectivity of 2.29 × 109cm Hz1∕2W−1at 9.6 μm, well above commercial detectors at the same operating temperature.
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Extending the Tunable Plasma Wavelength in III–V Semiconductors from the Mid‐Infrared to the Short‐Wave Infrared by Embedding Self‐Assembled ErAs Nanostructures in GaAs
Abstract The group III–V semiconductor photonic system is attractive to photonics engineers because it provides a complete set of photonic components. A plasmonic material that can be epitaxially integrated with the group III–V photonic system will potentially lead to many applications leveraging plasmonics and metamaterials. In this work, the shortest plasma wavelength ever reported in a III–V‐based material is demonstrated by epitaxially embedding ErAs into GaAs. This composite material acts as a tunable plasmonic material across the technologically important 2.68–6 µm infrared window. The growth window of this material is demonstrated to be much wider than other current heavily doped III–V plasmonic materials. Additionally, it is shown that the scattering rate can be reduced by increasing the growth temperature. The wide growth temperature range, designer plasmonic response, and the ease of epitaxial integration with other III–V semiconductor devices demonstrate the potential of ErAs:GaAs nanocomposites for the creation of a new type of metamaterial and other novel optoelectronic and nanophotonic applications.
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- Award ID(s):
- 1839056
- PAR ID:
- 10131485
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Optical Materials
- Volume:
- 8
- Issue:
- 7
- ISSN:
- 2195-1071
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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