Molecules are ubiquitous in natural phenomena and man-made products, but their use in quantum optical applications has been hampered by incoherent internal vibrations and other phononic interactions with their environment. We have now succeeded in turning an organic molecule into a coherent two-level quantum system by placing it in an optical microcavity. This allows several unprecedented observations such as 99\% extinction of a laser beam by a single molecule, saturation with less than 0.5 photon, and nonclassical generation of few-photon super-bunched light. Furthermore, we demonstrate efficient interaction of the molecule-microcavity system with single photons generated by a second molecule in a distant laboratory. Our achievements pave the way for linear and nonlinear quantum photonic circuits based on organic platforms.
@article{arxiv.1809.07526,
title = {Turning a molecule into a coherent two-level quantum system},
author = {Daqing Wang and Hrishikesh Kelkar and Diego Martin-Cano and Dominik Rattenbacher and Alexey Shkarin and Tobias Utikal and Stephan Götzinger and Vahid Sandoghdar},
journal= {arXiv preprint arXiv:1809.07526},
year = {2019}
}