Dark current and photocurrent analysis of plasmonic nano-antenna photodetector

Surface plasmonic resonance (SPR) plays important roles in performance enhancement in the Quantum Dot Infrared Photodetector. It can increase the photoresponse, SPR induced surface confinement and electromagnetic field enhancement. The angular dependence of the SPR enhancement effect has been fully investigated. In this thesis, the angular dependent effects of the two dimensional subwavelength hole array (2DSHA) and circular disk array (CDA) plasmonic structures are analyzed and compared with regular quantum dot photodetector. The photocurrent and dark current of both SPR structures are at different angles. The CDA plasmonic structure shows stronger angular dependence pattern than the 2DSHA plasmonic structure. The angular dependence is analyzed and agrees with the radiation pattern of a circular aperture antenna.