Open AccessOptical properties demonstrating strong coupling of compactly arranged Ge quantum dots
Author(s) -
Tong Zhou,
Zhenyang Zhong
Publication year - 2019
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.27.022173
Subject(s) - quantum dot , photoluminescence , delocalized electron , materials science , excitation , condensed matter physics , optoelectronics , coupling (piping) , quenching (fluorescence) , molecular physics , blueshift , optics , physics , fluorescence , quantum mechanics , metallurgy
Coupled quantum dots (QDs) have been extensively investigated for their unique collective properties and potential applications in optoelectronic devices. Herein, dense Ge QDs with a compact arrangement in-plane are readily obtained. Systematic studies on power-dependent photoluminescence (PL) from the QD ensemble demonstrate a PL peak with a superior intensity, a constant peak energy and width as a function of the excitation power. Moreover, the temperature-dependent PL spectra exhibit a pronounced red-shift and a rapid PL quenching with increasing temperature. Such PL properties are attributed to the formation of miniband and the delocalization of holes in the QD ensemble due to the strong coupling between closely adjacent QDs.