Quantum dots-in-a-well infrared photodetectors

@article{Krishna:PhysD2005, abstract = {Novel InAs/InGaAs quantum dots-in-a-well (DWELL) infrared photodetectors are reviewed. These detectors, in which the active region consists of InAs quantum dots (QDs) embedded in an InGaAs quantum well, represent a hybrid between a conventional quantum well infrared photodetector (QWIP) and a QD infrared photodetector (QDIP). Like QDIPs, DWELL detectors display normal incidence operation without gratings or optocouplers while demonstrating reproducible 'dial-in recipes' for control over the operating wavelength, like QWIPs. Using femtosecond spectroscopy, long carrier lifetimes have been observed in DWELL heterostructures, suggesting their potential for high temperature operation. Moreover, DWELL detectors have also demonstrated bias-tunability and multicolour operation in the mid-wave infrared (3-5 \&\#181;m), long-wave infrared (LWIR, 8-12 \&\#181;m) and very long-wave infrared (\>14 \&\#181;m) regimes. We have recently developed LWIR 320 \&\#215; 256 focal plane arrays operating at liquid nitrogen temperatures. One of the potential problems with these detectors is the low quantum efficiency, which translates into low responsivity and detectivity. Some solutions for mitigating these problems are suggested at the end of this paper.}, author = {Krishna, Sanjay}, citeulike-article-id = {3872593}, doi = {10.1088/0022-3727/38/13/010}, journal = {Journal of Physics D: Applied Physics}, keywords = {detector, dwell}, number = {13}, pages = {2142--2150}, posted-at = {2009-01-09 23:29:56}, priority = {2}, title = {Quantum dots-in-a-well infrared photodetectors}, url = {http://dx.doi.org/10.1088/0022-3727/38/13/010}, volume = {38}, year = {2005} }

TY - JOUR ID - Krishna:PhysD2005 L3 - citeulike-article-id:3872593 N2 - Novel InAs/InGaAs quantum dots-in-a-well (DWELL) infrared photodetectors are reviewed. These detectors, in which the active region consists of InAs quantum dots (QDs) embedded in an InGaAs quantum well, represent a hybrid between a conventional quantum well infrared photodetector (QWIP) and a QD infrared photodetector (QDIP). Like QDIPs, DWELL detectors display normal incidence operation without gratings or optocouplers while demonstrating reproducible 'dial-in recipes' for control over the operating wavelength, like QWIPs. Using femtosecond spectroscopy, long carrier lifetimes have been observed in DWELL heterostructures, suggesting their potential for high temperature operation. Moreover, DWELL detectors have also demonstrated bias-tunability and multicolour operation in the mid-wave infrared (3-5 µm), long-wave infrared (LWIR, 8-12 µm) and very long-wave infrared (>14 µm) regimes. We have recently developed LWIR 320 × 256 focal plane arrays operating at liquid nitrogen temperatures. One of the potential problems with these detectors is the low quantum efficiency, which translates into low responsivity and detectivity. Some solutions for mitigating these problems are suggested at the end of this paper. IS - 13 JF - Journal of Physics D: Applied Physics EP - 2150 TI - Quantum dots-in-a-well infrared photodetectors VL - 38 SP - 2142 KW - detector KW - dwell AU - Krishna, Sanjay PY - 2005/// UR - http://dx.doi.org/10.1088/0022-3727/38/13/010 ER -