Fundamental Noises and Sensitivity Limits of Interferometric Gravitational-Waves Detectors of a New Generation

The work is aimed at developing a new field of science – gravitational-wave astronomy and is devoted to the development of methods for increasing the sensitivity of new generation interferometric gravitational wave detectors based on: 1) reducing the level of fundamental noise in interferometer mirrors due to their cooling to low temperatures, reducing dissipation in mechanical oscillation modes and reducing optical absorption in mirrors, where monocrystalline high-purity silicon is chosen as the base material for the mirrors, although the possibility of using sapphire and other materials is not excluded; 2) development of effective methods for quantum measurements of the impact of gravitational waves on interferometer mirrors, allowing the impact of quantum noise in gravitational-wave interferometer signal recording systems to be reduced and the standard quantum sensitivity limit to be overcome, as well as methods for suppressing the effect of parametric oscillatory instability that occurs in gravitational-wave interferometers at high optical pumping powers. The theoretical analysis, based on the latest advances in quantum measurement theory and quantum optics, is combined with detailed experimental studies of optical absorption and mechanical dissipation processes in elements of gravitational-wave detectors.