posted on 2021-10-12, 13:37authored byArianne Brooks, Xiao-Liu Chu, Zhe Liu, Rüdiger Schott, Arne Ludwig, Andreas D. Wieck, Leonardo Midolo, Peter Lodahl, Nir Rotenberg
Tailored
photonics cavities enhance light–matter interactions,
ultimately enabling a fully coherent quantum interface. Here, we report
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 reroute
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.