Ultra-quiet mirrors for measurement systems at the quantum limit
The aim of this group is to develop technology essential for the creation of the next-generation of ultra-quiet suspended mirrors required for observation of quantum effects such as ground state cooling and optical and mechanical squeezing and entanglement, as well for the next-generation of upgrades to interferometric gravitational wave detectors.
The desired outcomes of our collaborative work are designs and experimental tests of novel ultra-quiet mirror systems for implementation in systems targeted at ultra-sensitive optical measurements of the position of macroscopic mirrors. This is an area in which both the AEI and Glasgow have complementary strengths and are recognised leaders.
The respective teams have outstanding capabilities in development of ultra-low thermal noise quasi-monolithic mirror suspensions, characterisation of material properties at cryogenic temperatures, development of high power laser sources and studies of the quantum mechanical coupling between light and mechanical oscillators.
By combining expertise and resources, the partners will form a world-leading group in the area, and this is essential for Northern Europe to play a major part in the next generation of ground based gravitational wave detectors.
In the initial 5 year period, the group will carry out a coordinated programme of research in the areas of studies of the properties of crystalline silicon, and techniques for developing quasi-monolithic silicon mirror suspensions.
When cooled to cryogenic temperatures silicon represents a highly interesting material for low-dissipation mirrors due to its combination of thermal and thermo-mechanical properties. However the temperature dependence of the optical properties of silicon, and the effects of commonly used doping on the absorption at relevant wavelengths, are almost entirely un-studied. Understanding the limitations to reducing Brownian noise in cooled silicon mirrors set by both intrinsic material effects and surface properties is also of key importance.
Central to the program are:
- Expertise and facilities in Glasgow for both room and cryogenic mechanical spectroscopy, and design and development of quasi-monolithic mirror suspension
- Expertise at the AEI in optical characterisation of low noise systems, including a dedicated high-stability, ultra-low noise test facility