AVS 63rd International Symposium & Exhibition
    MEMS and NEMS Wednesday Sessions
       Session MN+NS-WeA

Paper MN+NS-WeA3
Single Laser Modulated Drive and Detection of a Nano-Optomechanical Cantilever

Wednesday, November 9, 2016, 3:00 pm, Room 102B

Session: Optomechanics, Photonics, and Quantum Nanosystems
Presenter: Vincent Sauer, University of Alberta and The National Institute for Nanotechnology, Canada
Authors: V.T.K. Sauer, University of Alberta and The National Institute for Nanotechnology, Canada
J.N. Bachman, University of Alberta and The National Institute for Nanotechnology, Canada
Z. Diao, University of Alberta and The National Institute for Nanotechnology, Canada
M.R. Freeman, University of Alberta and The National Institute for Nanotechnology, Canada
W.K. Hiebert, University of Alberta and The National Institute for Nanotechnology, Canada
Correspondent: Click to Email
Nano-optomechanical systems (NOMS) offer many advantages in transducing nanomechanical motion including very high displacement sensitivities and large frequency detection bandwidths due to their optical nature. It follows from this that NOMS are a promising avenue for on-chip nanomechanical mass sensing. To take full advantage of the operational frequency properties that NOMS devices possess it is important to drive the devices optically as well. Here, a single laser modulated drive and detection (SLMDD) system is modeled and demonstrated. The setup operates similarly to a traditional NOMS pump/probe system, but instead of using a separate probe laser with a constant output power, the probe laser is power modulated to coherently drive the nanomechanical resonator using an optical gradient force. Using the SLMDD system the second laser source and its optical filter can be removed from a standard NOMS measurement system reducing the cost and complexity. This results in signal mixing between the modulated optical pump power and the Lorentzian response of the nanomechanical cantilever. The response at 1f gives a fano-like shape, but we are still able to track this characteristic mechanical frequency within a phase-lock loop. This demonstrates that the device could still be used for inertial mass loading experiments which rely on mechanical frequency tracking. Interestingly, the SLMDD system also enables homodyne detection through the DC response. As such, this can circumvent some difficulties of measuring high frequency devices with lower frequency equipment.