The Modulation Effect of Local Density of Optical States of Plasmonic Nanoantennas on their Photoluminescence
Chen-Hsien Huang1*, Fan-Cheng Lin1, Jer-Shing Huang1
1Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
* presenting author:振咸黃,
A gold plasmonic nanoantenna can provide additional local density of optical states (LDOS) for excited quantum emitters to radiative decay and thereby can shape the emission properties of the emitters. One example is the modulation of the antenna’s photoluminescence spectrum. Here, we fabricate gold nanoantennas with various size and study the modulation effect of gold nanoantennas systematically. Both symmetric and asymmetric nanoantennas are fabricated and studied. All of the antennas show obvious modulation effects on the photoluminescence spectrum due to the transverse resonance, antibonding, higher-order and fundamental longitudinal localized surface plasmon resonance mode. The spectral features are in good agreement with that in the spectra obtained from dark-field scattering and numerical simulations. In addition to excitation with 532 nm laser, exciting plasmonic gold nanoantennas with continuous wave laser at 633 nm also leads to strong photoluminescence and pronounced modulation effects. Our work shows that photoluminescence is strongly modulated by the LDOS of the nanoantennas and therefore can be used as a local luminescence source to report the LDOS.

Keywords: Nanoantennas, Plasmonic resonance, Photoluminescence