Open AccessTemperature dependence of photoluminescence properties of water-soluble ZnSe quantum dots
Author(s) -
Yong-Shin Lee,
Tomoyo Taniguchi,
DaeGwi Kim
Publication year - 2019
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1220/1/012024
Subject(s) - photoluminescence , exciton , quantum dot , excited state , quenching (fluorescence) , ground state , condensed matter physics , thermal , bound state , materials science , molecular physics , atomic physics , chemistry , physics , nanotechnology , optoelectronics , fluorescence , optics , quantum mechanics , thermodynamics
We have investigated the optical properties of ZnSe quantum dots (QDs) prepared by a hydrothermal method. The photoluminescence (PL)-decay profiles become slower with an increase in temperature up to 160 K, contrary to an ordinary behaviour due to thermal quenching. The temperature dependence of the PL-decay profile is explained by a three-state model consisting of a ground state and two excited states of the lower-lying bound-exciton and higher-lying dark-exciton states. The analysis of the temperature dependence of the decay time indicates that the dark-exciton state contributes to the PL-decay process in the ZnSe QDs.