In optomechanics, light is used to control and detect mechanical motion. In order to achieve quantum superposition states of motion, researchers are in search of a platform which promises strong coupling between light and motion at single-photon level.
Recently, Yuan et al. from the SteeleLab have introduced a new optomechanical platform based on 3D superconducting cavities in Nature Communications. For the first time, researchers couple the mechanical motion of a silicon nitride membrane to electromagnetic field inside the 3D microwave cavity. Exploiting the large quality factors of both the cavity and the membrane, they are able to use microwave photons to cool the motion of the millimetre scale membrane resonator, visible to the naked eye, to a record low mode temperature of 34 microkelvin.
The result demonstrates the potentials of 3D optomechanics. With optimization, this platform offers the possibility to reach the regime of single-photon strong coupling, opening up a new generation of experiments.
For more information, see the article on the Nature Communications website, as well as the press release from TU Delft.
Left: A silicon nitride membrane embedded in an aluminium 3D cavity. The membrane is held on a 5mm X 5mm silicon frame. Right: An optical microscope image looking from the top showing an aluminium coated silicon nitride membrane and the underlying aluminium antenna pads. The size of the membrane is 1mm X 1mm.