Quantum emitters for plasmonics
In the radio frequency range, antennas allow the emission of a resonant circuit to be directed to a receiver in a very controlled manner. In the optical frequency range, we do not have this option. Particle plasmons, the collective resonant oscillation of the electrons of a metal nanoparticle, are a promising candidates for antennas in the visible frequency range. However, it is not readily possible to apply the concepts of radio frequency technology to the optics because, for example, the losses in metals are much greater in the visible. In this project, the 'resonant circuit' is a single semiconductor quantum dot showing very stable photoemission. The 'antenna' is a metal nanoparticle that has been placed near it. The antenna modifies the radiation properties of the quantum dot, but also absorbs light. We can prove both effects by their influence on the statistics of the emitted photon current. Time-resolved single-photon counting will allow us to develop the optimum antenna for an emitter in the visible to very efficiently couple this emitter to, for example, a photodetector.