Cavity-enhanced optical detection of carbon nanotube Brownian motion

S. Stapfner, L. Ost, D. Hunger, J. Reichel, I. Favero, E. M. Weig
2013 Applied Physics Letters  
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
more » ... e in a scanning electron microscope. Our work successfully extends the principles of high-sensitivity optomechanical detection to molecular scale nanomechanical systems.
doi:10.1063/1.4802746 fatcat:yn5cbq77drb4leq44ll4up2qju