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Updated: Apr 1, 2026

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy
Published on: June 28, 2016
Strong quantum confinement effect and reduced Fröhlich exciton-phonon coupling in ZnO quantum dots embedded inside a
J Q Ning1, C C Zheng, X H Zhang
1Department of Physics, The University of Hong Kong, Pokfulam Road, Hong Kong, China. sjxu@hku.hk.
Abstract:
ZnO quantum dots (QDs) embedded in an amorphous SiO2 matrix were examined in depth by using variable-temperature photoluminescence (PL) and optical reflectance spectroscopies. Compared with ZnO bulk crystals, ZnO quantum dots with an average size of 4 nm exhibit a strong quantum confinement effect, evidenced by a large blue shift in both PL and reflectance peaks of excitons. More interestingly, a remarkably reduced long-range Fröhlich interaction was revealed in ZnO QDs. These fascinating effects may make ZnO QDs a very appealing system in the fields of optoelectronics and others.
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