Reducing Coating Thermal Noise in Gravitational Wave Detectors

American University, Washington DC

Investigators

Abstract

Direct detection of gravitational waves has been a major challenge in gravity and astrophysics research for nearly 50 years. Successful detection of gravitational waves is expected to provide insight and information on neutron stars, supernova explosions, black holes, and the earliest moments after the Big Bang that is not available to electromagnetic telescopes. It will also provide an experimental test of Einstein's General Theory of Relativity which can help determine if there are missing elements to our understanding of gravity and cosmology. The detection of astronomical gravitational waves requires extremely precise optical measurements. Coating thermal noise in the optics is a limiting noise source in the most sensitive frequency band of second generation gravitational wave detectors. This project is on the study and improvement of coating thermal noise through novel measurements of the mechanical loss in optical coating materials. Measuring two sources of dissipation (from bulk and torsional motion) in coating materials can give valuable information for low thermal noise coating design as well as insights into the causes of thermal noise in coating materials. Improvements in coating thermal noise will have applications beyond gravitational wave detection. Frequency stabilization, quantum mechanics experiments, and other precision optics applications are encountering the same coating thermal noise limitation as gravitational wave detection. Some of these have commercial and industrial applications, especially frequency stabilization and precision timing. In addition, this proposal helps to develop an experimental physics program at American University that will include undergraduate researchers. This will help expose American students (many of whom aspire to careers in public policy) to experimental science and cutting edge research.