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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Resonant cavity-enhanced photodetector incorporating a type-II superlattice to extend MWIR sensitivity
AU - Letka, Veronica
AU - Bainbridge, Andrew
AU - Craig, Adam
AU - Al-Saymari, Furat
AU - Marshall, Andrew
PY - 2019/8/19
Y1 - 2019/8/19
N2 - Mid-infrared resonant cavity-enhanced photodetectors (RCE PD) present a promising technology for targeted gas detection. We demonstrate an RCE PD incorporating an InAs/InAsSb superlattice as the detecting element, extending the resonant wavelength beyond 4 µm. AlAsSb/GaSb mirrors and a unipolar barrier active region paralleling an nBn structure are also used, and performance is compared to a conventional broadband nBn detector incorporating the same superlattice. The RCE PD exhibited a Q-factor of ∼90 and an extremely stable resonance wavelength. Peak responsivity was 3.0 A W−1 at 240 K, equalling 84% quantum efficiency, a 5.5 times increase over the reference nBn at the same wavelength. Dark current density was 3.3×10−2 A cm−2 at 240 K, falling to 2.7×10−4 A cm−2 at 180 K. The broadband BLIP limit is approached at 180 K with specific detectivity of 2.1×1011 cm Hz1/2 W−1 , which presents thepotential of achieving BLIP-limited operation in the thermoelectric cooling regime.
AB - Mid-infrared resonant cavity-enhanced photodetectors (RCE PD) present a promising technology for targeted gas detection. We demonstrate an RCE PD incorporating an InAs/InAsSb superlattice as the detecting element, extending the resonant wavelength beyond 4 µm. AlAsSb/GaSb mirrors and a unipolar barrier active region paralleling an nBn structure are also used, and performance is compared to a conventional broadband nBn detector incorporating the same superlattice. The RCE PD exhibited a Q-factor of ∼90 and an extremely stable resonance wavelength. Peak responsivity was 3.0 A W−1 at 240 K, equalling 84% quantum efficiency, a 5.5 times increase over the reference nBn at the same wavelength. Dark current density was 3.3×10−2 A cm−2 at 240 K, falling to 2.7×10−4 A cm−2 at 180 K. The broadband BLIP limit is approached at 180 K with specific detectivity of 2.1×1011 cm Hz1/2 W−1 , which presents thepotential of achieving BLIP-limited operation in the thermoelectric cooling regime.
U2 - 10.1364/OE.27.023970
DO - 10.1364/OE.27.023970
M3 - Journal article
VL - 27
SP - 23970
EP - 23980
JO - Optics Express
JF - Optics Express
SN - 1094-4087
IS - 17
ER -