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Title: Deep level centers and their role in photoconductivity transients of InGaAs/GaAs quantum dot chains

The in-plane photoconductivity and photoluminescence are investigated in quantum dot-chain InGaAs/GaAs heterostructures. Different photoconductivity transients resulting from spectrally selecting photoexcitation of InGaAs QDs, GaAs spacers, or EL2 centers were observed. Persistent photoconductivity was observed at 80 K after excitation of electron-hole pairs due to interband transitions in both the InGaAs QDs and the GaAs matrix. Giant optically induced quenching of in-plane conductivity driven by recharging of EL2 centers is observed in the spectral range from 0.83 eV to 1.0 eV. Conductivity loss under photoexcitation is discussed in terms of carrier localization by analogy with carrier distribution in disordered media.
Authors:
;  [1] ; ; ; ; ; ;  [2]
  1. Department of Physics, Taras Shevchenko National University of Kyiv, 64 Volodymyrs'ka St., Kyiv 01601 (Ukraine)
  2. Institute for Nanoscience and Engineering, University of Arkansas, 731 W. Dickson St., Fayetteville, Arkansas 72701 (United States)
Publication Date:
OSTI Identifier:
22402666
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 116; Journal Issue: 19; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; DISTRIBUTION; GALLIUM ARSENIDES; HOLES; INDIUM ARSENIDES; PHOTOCONDUCTIVITY; PHOTOLUMINESCENCE; QUANTUM DOTS; QUENCHING; SPACERS; TRANSIENTS