Simulations of the effect of waveguide cross-section on quantum dot-plasmon coupling

Quantum dot-plasmonwaveguide systems are of interest for the active control of plasmon propagation, and consequently, the development of active nanophotonic devices such as nano-sized optical transistors. This paper is concerned with how varying aspect ratio of the waveguide cross-section affects the quantum dot-plasmon coupling. We compare a stripe waveguide with an equivalent nanowire, illustrating that both waveguides have a similar coupling strength to a nearby quantum dot for small waveguide cross-section, thereby indicating that stripe lithographic waveguides have strong potential use in quantum dot-plasmonwaveguide systems. We also demonstrate that changing the aspect ratio of both stripe and wirewaveguides can increase the spontaneous emission rate of the quantum dot into the plasmon mode, by up to a factor of five. The results of this paper will contribute to the optimisation of quantum dot-plasmonwaveguide systems and help pave the way for the development of active nanophotonics devices.