Photo-instability of CdSe/ZnS quantum dots in poly(methylmethacrylate) film

Journal Article · Sat Dec 28 04:00:00 EST 2013 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.4857055· OSTI ID:22217728

Zhang, Hongyi; Liu, Yu; Ye, Xiaoling; Chen, Yonghai ^[1]

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1. Key Laboratory of Semiconductor Materials Science and Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Institute of Semiconductors, Chinese Academy of Sciences, P.O. Box 912, Beijing 100083 (China)

The photo-instability of CdSe/ZnS quantum dots (QDs) has been studied under varied conditions. We discussed the main features of the evolution of photoluminescence (PL) intensity and energy at different laser powers, which showed critical dependences on the environment. The PL red shift in a vacuum showed strong temperature dependence, from which we concluded that the thermal activation energy for trapping states of the charge carriers was about 14.7 meV. Furthermore, the PL spectra showed asymmetric evolution during the laser irradiation, for which two possible explanations were discussed. Those results provided a comprehensive picture for the photo-instability of the colloidal QDs under different conditions.

• OSTI ID: 22217728
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 24 Vol. 114; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ACTIVATION ENERGY
CADMIUM SELENIDES
CHARGE CARRIERS
FILMS
INSTABILITY
LASER RADIATION
MEV RANGE
PHOTOLUMINESCENCE
QUANTUM DOTS
RED SHIFT
SEMICONDUCTOR MATERIALS
SPECTRA
TEMPERATURE DEPENDENCE
TRAPPING
ZINC SULFIDES