Organic Molecules Coming of Age in Quantum Optics
Abstract: The interaction of light and matter at the nanometer scale lies at the heart of quantum optics because it concerns elementary processes such as absorption or emission of a photon by an atom. Over the past decade, we have shown that direct coupling of a photon to a single two-level atom should be possible via tight focusing . However, because transitions in quantum emitters are typically not closed, laboratory demonstrations of this idea fall short of the theoretical prediction. I shall report on recent achievements, where the branching ratio of a single organic molecule is improved by a substantial Purcell effect when coupled to a microcavity [2-4]. Furthermore, we will discuss coherent linear and nonlinear experiments  on molecules coupled to subwavelength waveguides . Indeed, many interesting proposals in quantum optics and light-matter interaction rely on having multiple quantum emitters well-coupled to a single mode of light . We show that one-dimensional photonic channels including microresonator elements on a chip are ideal for coupling several identical emitters . Together with their ability to generate narrowband stream of single photons, these developments make organic molecules viable candidates for integration in chip-based quantum optical circuits.
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Host: Glenn Solomon