Time-resolved, surface-enhanced, coherent anti-Stokes Raman spectroscopy (tr-SECARS) isideally suited for preparing and interrogating vibrational coherences on single molecules.We have succeeded in the rst demonstration of this concept through measurements carriedout on molecules attached to gold nanosphere pairs which act as plasmonic nano-dumbellantennae. The tr-SECARS traces provide unique signatures of coherent evolution in discreteensembles. The signals are characterized by phase and amplitude noise, which can be cast interms of amplitude probability distribution functions (PDF), which allow rigorous distinctionbetween single, few, and many molecule coherences. We give a brief background on tr-CARS,the experimental system for carrying out tr-SECARS and the analysis of the results in termsof PDFs. The analysis makes it clear that we have, for the rst time, observed the coherentvibrational motion of a single molecule
