Laser cooling of a micromechanical membrane to the quantum backaction limit

Understand

The radiation pressure of light can act to damp and cool the vibrational motion of a mechanical resonator.

• In understanding the quantum limits of this cooling, one must consider the effect of shot noise fluctuations on the final thermal occupation.
• In optomechanical sideband cooling in a cavity, the finite Stokes Raman scattering defined by the cavity linewidth combined with shot noise fluctuations dictates a quantum backaction limit, analogous to the Doppler limit of atomic laser cooling.
• In our work we sideband cool to the quantum backaction limit by using a micromechanical membrane precooled in a dilution refrigerator.