skip to main content

SciTech ConnectSciTech Connect

Title: Size dependence of electron spin dephasing in InGaAs quantum dots

We investigate ensemble electron spin dephasing in self-assembled InGaAs/GaAs quantum dots (QDs) of different lateral sizes by employing optical Hanle measurements. Using low excitation power, we are able to obtain a spin dephasing time T{sub 2}{sup *} (in the order of ns) of the resident electron after recombination of negative trions in the QDs. We show that T{sub 2}{sup *} is determined by the hyperfine field arising from the frozen fluctuation of nuclear spins, which scales with the size of QDs following the Merkulov-Efros-Rosen model. This scaling no longer holds in large QDs, most likely due to a breakdown in the lateral electron confinement.
Authors:
; ; ;  [1] ; ; ; ;  [2]
  1. Department of Physics, Chemistry and Biology, Linköping University, S-581 83 Linköping (Sweden)
  2. Graduate School of Information Science and Technology, Hokkaido University, Kita 14, Nishi 9, Kita-ku, Sapporo 060-0814 (Japan)
Publication Date:
OSTI Identifier:
22412769
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 106; Journal Issue: 9; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; CONFINEMENT; ELECTRONS; EXCITATION; FLUCTUATIONS; GALLIUM ARSENIDES; INDIUM ARSENIDES; INTERFACES; QUANTUM DOTS; RECOMBINATION; SPIN