On-chip interferometric detection of nanomechanical motion

Abstract

An integrable on-chip displacement transduction of nanomechenical motion is developed that senses the modulation of the optical near-field of an illuminated vibrating string with a nearby Schottky photodiode. This scheme poses no restrictions on resonator material and avoids additional damping. The achieved sensitivity of l pm/Hz1/2 enables the detection of Brownian motion of our mechanical resonators at room temperature. Implementing a feedback scheme of the detected signal into the electrical actuation, we demonstrate self-oscillation. © 2010 American Chemical Society.