Optical cavities with small mode volume are well-suited to detect the
vibration of sub-wavelength sized objects. Here we employ a fiber-based,
high-finesse optical microcavity to detect the Brownian motion of a freely
suspended carbon nanotube at room temperature under vacuum. The optical
detection resolves deflections of the oscillating tube down to 50pm/Hz^1/2. A
full vibrational spectrum of the carbon nanotube is obtained and confirmed by
characterization of the same device in a scanning electron microscope. Our work
successfully extends the principles of high-sensitivity optomechanical
detection to molecular scale nanomechanical systems.Comment: 14 pages, 11 figure
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.