Dr Graeme McGhee

Dr McGhee earned a Master's degree in Physics with Astrophysics from the University of Glasgow in 2019, after which he obtained a PhD at Glasgow's Institute for Gravitational Research, focusing on the challenging task of improving the sensitivity of gravitational wave detectors. He won multiple competitive fellowships to launch collaborative projects at various institutions worldwide, to develop numerous state-of-the-art high-quality low-loss optics. He won the Royal Astronomical Society's best thesis prize. Since 2024 he has been a post-doctoral researcher at the University of Glasgow and a JSPS Fellow at the University of Toyama. He contributes to global efforts to improve the sensitivity of gravitational wave detectors, working on LIGO and Virgo, and the future European Einstein Telescope.

While the first direct detection of gravitational waves in 2015 opened a new window in astrophysics, the sensitivity of current detectors must be significantly increased to detect more distant, weaker, and perhaps as yet unrealised astronomical sources.

Dr McGhee addressed the need for new technological advances for gravitational wave detectors. Currently, the dominant noise source is the thermal noise of the mirror coatings, which induces vibrations on the molecular level. Dr McGhee investigated new mirror coating material candidates to improve the sensitivity of current detectors via a reduction in coating thermal noise. He launched a comprehensive study of novel titania-doped-silica mirror coatings, which cemented its efficacy as one of the most promising materials for future detectors. He also helped develop titania-doped-germania based highly reflective mirror coatings deposited with an improved defect-free recipe, performing the first mechanical loss measurements of these to verify their thermal noise reduction. This material is of great interest for the very next gravitational wave detector upgrades. These studies have already inspired follow-up investigations for the LIGO and Virgo scientific collaborations. Improved mirrors that provide greater sensitivity will allow us to observe merging neutron stars from further away than ever before, detect events from earlier in history of the Universe, and make many more multi-messenger observations. Such observations will provide further tests of general relativity, tighten constraints on the equation-of-state of neutron stars, and offer new cosmological insights into the expansion rate of the Universe.

The work was conducted at the University of Glasgow (Scotland), Université Claude Bernard Lyon 1 (France), California Institute of Technology and California State University Fullerton (USA).