Optical coating optimisation to enable the transfer of technologies from gravitational wave detection to quantum and intense light-matter experiments

Some of the most exciting experiments planned in the UK and internationally - from studying extreme light-matter interactions, to the exploitation of quantum technologies - are demanding unpreceded performance in mirror coating technology. Optical thin film coatings appear ubiquitously in the technology around us, however current available performances will not meet the requirements for, and will thus limit the exploitation from, many of these experiments. For example, emerging extreme light-matter experiments are now handling power densities an order of magnitude higher than those previously achieved. This includes major UK infrastructures, including the Central Laser Facility (CLF) and the Scottish Centre for the Application of Plasma-based Accelerators (SCAPA), in addition to partnership initiatives in Europe including the 850MEuro European funded Extreme Light Infrastructure (ELI). All these experiments will soon require laser damage threshold (LDT) performance in the highly reflective mirrors at a level not currently available. This proposal, for the first time, will seek to exploit advanced optical coating technologies, developed with the field of gravitational wave astronomy, for use in intense-light matter experiments. Moreover, the capabilities developed will significantly support existing activities within the Quantum Technologies for Fundamental Physics (QTFP) and the UK's continued effort in gravitational wave astronomy.