Coherent coupling of a single molecule to a scanning Fabry-Perot   microcavity
  Organic dye molecules have been used in great many scientific and technological applications, but their wider use in quantum optics has been hampered by transitions to short-lived vibrational levels, which limit their coherence properties. To remedy this, one can take advantage of optical resonators. Here we present the first results on coherent molecule-resonator coupling, where a single polycyclic aromatic hydrocarbon molecule extinguishes 38\% of the light entering a microcavity at liquid helium temperature. We also demonstrate four-fold improvement of single-molecule stimulated emission compared to free-space focusing and set the ground for coherent mechanical manipulation of the molecular transition. Our experimental approach based on a microcavity of low mode volume and low quality factor paves the way for the realization of various nonlinear and collective quantum optical effects with molecules. 
Daqing Wang, Hrishikesh Kelkar, Diego Martin-Cano, Tobias Utikal,   Stephan G\"otzinger, Vahid Sandoghdar
quant-ph physics.atom-ph physics.optics