Tailored photonic cavities allow enhancing light-matter interaction ultimately to create a fully coherent quantum interface. Here, we report on an integrated microdisk cavity containing self-assembled quantum dots to coherently route photons between different access waveguides. We measure a Purcell factor of Fexp=6.9±0.9 for a cavity quality factor of about 10,000, allowing us to observe clear signatures of coherent scattering of photons by the quantum dots. We show how this integrated system can coherently re-route photons between the drop and bus ports, and how this routing is controlled by detuning the quantum dot and resonator, or through the strength of the excitation beam, where a critical photon number less than one photon per lifetime is required. We discuss the strengths and limitations of this approach, focusing on how the coherent scattering and single-photon nonlinearity can be used to increase the efficiency of quantum devices such as routers or Bell-state analyzers.
@article{arxiv.2107.12188,
title = {An integrated whispering-gallery-mode resonator for solid-state coherent quantum photonics},
author = {Arianne Brooks and Xiao-Liu Chu and Zhe Liu and Rudiger Schott and Arne Ludwig and Andreas D. Wieck and Leonardo Midolo and Peter Lodahl and Nir Rotenberg},
journal= {arXiv preprint arXiv:2107.12188},
year = {2021}
}