LAUSR

Photon emission is the hallmark of light-matter interaction and the foundation of photonic quantum science, enabling advanced sources for quantum communication and computing. Although single-emitter radiation can be tailored by the photonic environment, the introduction of multiple emitters extends this picture. A fundamental challenge, however, is that the radiative dipole-dipole coupling rapidly decays with spatial separation, typically within a fraction of the optical wavelength. We realize distant dipole-dipole radiative coupling with pairs of solid-state optical quantum emitters embedded in a nanophotonic waveguide. We dynamically probe the collective response and identify both super- and subradiant emission as well as means to control the dynamics by proper excitation techniques. Our work constitutes a foundational step toward multiemitter applications for scalable quantum-information processing. Description Coupling at a distance The merger of nanophotonics with quantum optics has provided a platform for the development of deterministic single-photon sources and sources of entangled photons. Tiranov et al. show that multiple quantum emitters (two or three quantum dots) can be coupled through a photonic crystal waveguide. The waveguide helps to overcome the typically short-range nature of the dipole-dipole interactions and allows the signature properties of such a coupled system, subradiant and superradiant emission, to be observed. Control of such processes could provide an enabling step for scaling up deterministic solid-state photon-emitter interfaces and multiphoton-entangled sources for applications in quantum information processing. —ISO A photonic crystal waveguide enables distant coupling between multiple solid-state optical quantum emitters.