title: Quantum Yield of Single Surface Plasmons Generated by a Quantum Dot Coupled with a Silver Nanowire.
abstract: The interactions between surface plasmons (SPs) in metal nanostructures and excitons in quantum emitters (QEs) lead to many interesting phenomena and potential applications that are strongly dependent on the quantum yield of SPs. The difficulty in distinguishing all the possible exciton recombination channels hinders the experimental determination of SP quantum yield. Here, we experimentally measured for the first time the quantum yield of single SPs generated by the exciton-plasmon coupling in a system composed of a single quantum dot and a silver nanowire (NW). By utilizing the SP guiding property of the NW, the decay rates of all the exciton recombination channels, i.e., direct free space radiation channel, SP generation channel, and nonradiative damping channel, are quantitatively obtained. It is determined that the optimum emitter-NW coupling distance for the largest SP quantum yield is about 10 nm, resulting from the different distance-dependent decay rates of the three channels. These results are important for manipulating the coupling between plasmonic nanostructures and QEs and developing on-chip quantum plasmonic devices for potential nanophotonic and quantum information applications.
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Li
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Wei
authors.affiliation: Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences , Beijing 100190, China.|Center for Nanoscience and Nanotechnology, School of Physics and Technology, and Institute for Advanced Studies, Wuhan University , Wuhan 430072, China.
authors.forename: Hongxing
authors.initials: H
authors.lastname: Xu
keywords: Quantum dot; decay rates; exciton; quantum yield; silver nanowire; surface plasmons