A window into the quantum level
Across the different fields of scientific research and physics, quantum mechanical phenomena involved in mechanical objects are revealing themselves slowly but surely. We are closer than ever to observing these various phenomena, whether on the nanometre scale, centimetre scale or kilometre scale, i.e. from tiny scale oscillators to large gravity wave detectors. As scientists involved in these fields report their findings independently, it is becoming clearer that a unified picture and common set of goals related to quantum effects in mechanical systems must emerge. Novel laser cooling techniques have made these quantum phenomena such as quantum back-action, ground state cooling and non-classical states of motion manifest themselves more readily. This may even herald a new research field called quantum optomechanics. In more technical terms, the project team is aiming to observe quantum mechanical phenomena relating to macroscopic mechanical objects. It is working on displaying quantum phenomena of mechanical objects in the form of toroidal monolithic microcavities. The 'Quantum optomechanics using monolithic micro-resonators' (QUOM) team has already achieved its goals, thanks in part to the development of a cryogenic apparatus to preserve microcavities at low temperatures and observe the results. The team also studied microstructures using a new technique that measures optomechanical properties at very low light intensities. Numerous results at a fine level of granularity and accuracy have been gleaned from these experiments, using novel laboratory methods and techniques. Advances have included new ultra sensitive detection schemes, development of optical resonances sensitive to nano-resonator motion and much more. Another important experiment involved Helium 3, which brought to light many interesting results, new effects and useful observations. These are allowing for other important experiments to be conducted, shedding much light on optomechanics and the quantum field. With this, observation of quantum radiation pressure noise, i.e. measurements beyond the standard quantum limit should in principle be possible, and so will other quantum signatures such as quantum friction. This project has set the pace for these discoveries, and the few years to come will be very interesting in this respect.
