Enhanced Single-Photon Emission from Single Quantum Dots Interacting with a One-Dimensional Plasmonic Chip

Modification of the photoluminescence (PL) behavior of a single colloidal quantum dot (QD) using plasmonic nanostructures has attracted considerable attention. Here, we attempted to control the PL behavior of a single CdSe/ZnS QD by using a one-dimensional plasmonic chip (1D-PC) with the simplest Ag grating pattern. By optimizing the distance between the single QD and 1D-PC, the PL intensity of the single QD was successfully enhanced 5 times with maintaining single-photon emission via enhancement of the excitation rate due to the electric field of the surface plasmon on the 1D-PC. On the other hand, control of the emission photon statistics, that is, single-photon emission and multiphoton emission, from the single QD was difficult because enhancement of the radiative rate of the single QD was not achieved by the 1D-PC. These results indicate that the 1D-PC is an attractive plasmonic nanostructure to obtain efficient single-photon emission which is indispensable for next-generation quantum information technologies.