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Title: Modeling of the quantum dot filling and the dark current of quantum dot infrared photodetectors

A generalized drift-diffusion model for the calculation of both the quantum dot filling profile and the dark current of quantum dot infrared photodetectors is proposed. The confined electrons inside the quantum dots produce a space-charge potential barrier between the two contacts, which controls the quantum dot filling and limits the dark current in the device. The results of the model reasonably agree with a published experimental work. It is found that increasing either the doping level or the temperature results in an exponential increase of the dark current. The quantum dot filling turns out to be nonuniform, with a dot near the contacts containing more electrons than one in the middle of the device where the dot occupation approximately equals the number of doping atoms per dot, which means that quantum dots away from contacts will be nearly unoccupied if the active region is undoped.
Authors:
; ;  [1]
  1. Department of Engineering Mathematics and Physics, Faculty of Engineering, Cairo University, Giza (Egypt)
Publication Date:
OSTI Identifier:
22278076
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 6; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; APPROXIMATIONS; ATOMS; COMPUTERIZED SIMULATION; DIFFUSION; ELECTRIC CURRENTS; ELECTRONS; PHOTODETECTORS; POTENTIALS; QUANTUM DOTS; SPACE CHARGE