Open AccessCorrelation between photoluminescence and morphology for single layer self-assembled InGaAs/GaAs quantum dots
Author(s) -
Baolai Liang,
Qing Yuan,
Linlin Su,
Ying Wang,
Yukun Guo,
Shufang Wang,
Guangsheng Fu,
E. Marega,
Yuriy I. Mazur,
Morgan E. Ware,
Gregory J. Salamo
Publication year - 2018
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.023107
Subject(s) - photoluminescence , quantum dot , materials science , laser linewidth , optoelectronics , gallium arsenide , anisotropy , excitation , nanophotonics , molecular physics , optics , laser , chemistry , physics , quantum mechanics
Single layer self-assembled InGaAs quantum dots (QDs) are manipulated by using different arsenic species on GaAs (100) surface. The As 4 molecules are experimentally observed to be more promising than As 2 to promote the formation of one-dimensionally-aligned QD-chain arrays. The lateral alignment of QDs and the corresponding formation of dot chains are explained by the anisotropic surface kinetics in combination with the different reactivities of the two molecules with bonding sites on the GaAs (100) surface. Photoluminescence (PL) measurements demonstrate that the spectra of the QD-chains broaden to higher energy and increases in intensity with increasing excitation laser power. The PL band of the QD-chains also exhibits a 9 meV reduction in linewidth as temperature increases starting from 8 K. These observations confirm an efficient lateral coupling between neighboring QDs and thereafter polarized QD emission, whereas the randomly distributed QDs grown with As 2 show no preferential polarization. Such QD-chains exhibiting anisotropic properties have the potential for nanophotonics applications like electro-optic modulators with very low drive voltage and ultra-wide bandwidth operation.