Influence of laser power on photoluminescence of hexagonal ZnO nanodisks.
Raman scattering and photoluminescence spectra of hexagonal ZnO nanodisks were investigated. Normal Raman spectrum shows the intense E2 modes, which confirms a typical wurtzite structure. The broadened E2 vibration peak is due to surface/interface defect in ZnO crystal. The influence of laser irradiation heating effect on emission intensity and position has been investigated by power dependent PL and resonant Raman scattering. The threshold value of the power density for laser heating effect is 2 kW/cm2. The shift of LO phonon vibrational peaks from RRS with excitation laser power also confirms laser irradiation heating effect. Beyond the threshold value of power density, the PL intensity and position will be affected by laser heating effect.
School of Chemistry and Environment, Beijing University of Aeronautics and Astronautics, Beijing 100191, China.
Penggang
P
Yin
Rui
R
Zhang
Ning
N
Wang
Lidong
L
Li
Lin
L
Guo