Multiplexed single photon source based on multiple quantum dots embedded within a single nanowire.

Photonics-based quantum information technologies require efficient, high emission rate sources of single photons. Position-controlled quantum dots embedded within a broadband nanowire waveguide provide a fully scalable route to fabricating highly efficient single photon sources. However, emission rates for single photon devices are limited by radiative recombination lifetimes. Here we demonstrate a multiplexed single photon source based on a multi-dot nanowire. Using epitaxially grown nanowires, we incorporate multiple energy-tuned dots, each optimally positioned within the nanowire waveguide, and providing single photons with high efficiency. This linear scaling of the single photon emission rate with number of emitters is demonstrated using a five-dot nanowire with an average multiphoton emission probability of <4% when excited at saturation. This represents the first ever demonstration of multiple single photon emitters deterministically incorporated in a single photonic device, and is a major step towards achieving GHz single photon emission rates from a scalable multi-quantum dot system.