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Title: Development of high-speed quantum dots/graphene infrared detectors for uncooled infrared imaging
Colloidal semiconductor quantum dots/graphene van der Waals (vdW) heterojunctions take advantages of the enhanced light-matter interaction and spectral tenability of quantum dots (QDs) and superior charge mobility in graphene, providing a promising alternative for uncooled infrared photodetectors with a gain or external quantum efficiency up to 1010. In these QD/graphene vdW heterostructures, the QD/graphene interface plays a critical role in controlling the optoelectronic process including exciton dissociation, charge injection and transport. Specifically, charge traps at the vdW interface can increase the noise, reduce the responsivity and response speed. This paper highlight our recent progress in engineering the vdW heterojunction interface towards more efficient charge transfer for higher photoresponsivity, D* and response speed. These results illustrate that the importance in vdW heterojunction interface engineering in QD/graphene photodetectors which may provide a promising pathway for low-cost, printable and flexible infrared detectors and imaging systems.
Authors:
; ; ;
Editors:
Fulop, Gabor F.; Kimata, Masafumi; Zheng, Lucy; Andresen, Bjørn F.; Miller, John Lester
Award ID(s):
1909292 1809293 1508494
Publication Date:
NSF-PAR ID:
10225244
Journal Name:
Infrared Technology and Applications XLVII, Vol 117410F (2021) SPIE Defense + Commercial Sensing (2021)
Page Range or eLocation-ID:
8
Sponsoring Org:
National Science Foundation
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