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First observation with global network of optical atomic clocks aimed for a dark matter detection



P. Wcislo, P. Ablewski, Kyle Beloy, S. Bilicki, M. Bober, Roger Brown, Robert J. Fasano, R. Ciurylo, H. Hachisu, T. Ido, J. Lodewyck, Andrew Ludlow, Will McGrew, P. Morzynski, Daniele Nicolodi, Marco Schioppo, M. Sekido, R. Le Targat, P. Wolf, Xiaogang Zhang, B. Zjawin, M. Zawada


We report on the first earth-scale quantum sensor network based on optical atomic clocks aimed at dark matter (DM) detection. Exploiting differences in the susceptibilities to the fine- structure constant of essential parts of an optical atomic clock, i.e. the cold atoms and the optical reference cavity, we can perform sensitive searches for dark matter signatures without the need of real-time comparisons of the clocks. We report a two orders of magnitude improvement in constraints on transient variations of the fine-structure constant, which considerably improves the detection limit for the standard model (SM) - DM coupling. We use Yb and Sr optical atomic clocks at four laboratories on three continents to search for both topological defect (TD) and massive scalar field candidates. No signal consistent with a dark- matter coupling is identified, leading to significantly improved constraints on the DM-SM couplings.
Science Advances


atomic clock, dark matter, fine structure constant, lattice clock, optical clock, strontium, ytterbium


Wcislo, P. , Ablewski, P. , Beloy, K. , Bilicki, S. , Bober, M. , Brown, R. , Fasano, R. , Ciurylo, R. , Hachisu, H. , Ido, T. , Lodewyck, J. , Ludlow, A. , McGrew, W. , Morzynski, P. , Nicolodi, D. , Schioppo, M. , Sekido, M. , Le Targat, R. , Wolf, P. , Zhang, X. , Zjawin, B. and Zawada, M. (2019), First observation with global network of optical atomic clocks aimed for a dark matter detection, Science Advances, [online], (Accessed August 15, 2022)
Created January 29, 2019, Updated October 12, 2021