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Plasmonic materials, and their ability to enable strong concentration of optical fields, have offered a tantalizing foundation for the demonstration of sub-diffraction-limit photonic devices. However, practical and scalable plasmonic optoelectronics for real world applications remain elusive. In this work, we present an infrared photodetector leveraging a device architecture consisting of a “designer” epitaxial plasmonic metal integrated with a quantum-engineered detector structure, all in a mature III-V semiconductor material system. Incident light is coupled into surface plasmon-polariton modes at the detector/designer metal interface, and the strong confinement of these modes allows for a sub-diffractive ( ) detector absorber layer thickness, effectively decoupling the detector’s absorption efficiency and dark current. We demonstrate high-performance detectors operating at non-cryogenic temperatures ( ), without sacrificing external quantum efficiency, and superior to well-established and commercially available detectors. This work provides a practical and scalable plasmonic optoelectronic device architecture with real world mid-infrared applications.
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High operating temperature plasmonic infrared detectors
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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- Award ID(s):
- 1926187
- PAR ID:
- 10363744
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- Applied Physics Letters
- Volume:
- 120
- Issue:
- 10
- ISSN:
- 0003-6951
- Page Range / eLocation ID:
- Article No. 101103
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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