CAREER: Developing Techniques for Atom-Based Gravitational Wave Detection and Dark Matter Searches with a Multiplexed Optical Lattice Clock

About This Grant

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). General audience abstract: Optical atomic clocks are now the most precise and accurate tabletop measurement devices ever constructed by humankind, offering sensitivity to new and exotic physics. The PI has recently developed a new kind of atomic clock apparatus and has used it to demonstrate a comparison between two optical clocks at a precision below one part in 10^19. To give a sense of scale, this corresponds to resolving a difference in the rate the two clocks tick at that would result in them disagreeing with each other by only 1 second after 300 billion years. The PI and a graduate student will use this new apparatus to develop and test ways to use optical atomic clocks to search for dark matter and to detect gravitational waves. This project therefore has the potential to result in new tools for studying the universe through gravitational wave astronomy, and new ways to search for answers to one of the biggest mysteries in physics, the nature of dark matter. The PI will integrate these research topics into new demos and hands-on activities designed to introduce K-12 students to modern physics concepts. Students will engage with these activities at live shows and interactive events as part of the University of Wisconsin “Wonders of Physics” outreach program, with an emphasis on reaching rural communities and Native American reservations in Wisconsin. This project will thereby strengthen public support for modern physics research and help students develop intuition for atomic technologies and their applications. Technical audience abstract: This research project aims to explore and develop emerging applications of optical atomic clocks. The PI has recently demonstrated a first-of-its-kind “multiplexed" optical lattice clock apparatus that enables differential clock comparisons between two or more spatially resolved ensembles of strontium atoms within the same vacuum chamber. These differential measurements eliminate the detrimental effects of clock laser noise and common mode environmental fluctuations, pushing the limits of achievable clock stability and atom-atom coherence. Record differential clock stabilities and fractional frequency precision have now been demonstrated in this apparatus, with a clear path to further gains in performance. The PI and collaborators will use this multiplexed optical lattice clock to develop and demonstrate novel measurement sequences and data analysis techniques for future gravitational wave detection with space-based optical lattice clocks, including the blind injection of simulated gravitational wave signals at realistic strengths. The PI and collaborators will also use the multiplexed optical lattice clock to search for foggy dark matter in previously unexplored regions of parameter space, and to develop new techniques to search for other forms of dark matter. The PI will work with collaborators to develop interactive and engaging demos and inquiry-based activities to introduce K-12 students to modern physics concepts, including the basic principles of atomic clocks and their applications, and will assess their effectiveness using surveys. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.