Observation of quantum motion of a nanomechanical resonator

Phys Rev Lett. 2012 Jan 20;108(3):033602. doi: 10.1103/PhysRevLett.108.033602. Epub 2012 Jan 17.


In this Letter we use resolved sideband laser cooling to cool a mesoscopic mechanical resonator to near its quantum ground state (phonon occupancy 2.6±0.2), and observe the motional sidebands generated on a second probe laser. Asymmetry in the sideband amplitudes provides a direct measure of the displacement noise power associated with quantum zero-point fluctuations of the nanomechanical resonator, and allows for an intrinsic calibration of the phonon occupation number.