The event will take stock of the developing international landscape of large-scale Atom Interferometer prototypes and discuss their synergies and complementarity. Such devices will be able to detect ultralight dark matter and gravitational waves in the mid-frequency band, complementing the capabilities of optical interferometers on Earth and the future LISA space mission, and offering unique sensitivity to ultralight bosonic dark matter.
The main goals of the workshop will be to develop a Roadmap for the design and technology choices for one or several km-scale atom interferometers to be ready for operation in the mid 2030s, which is supported by the cold atom community and the potential user communities interested in its science goals. This Roadmap will outline technological milestones as well as refine interim and long-term scientific goals.
Further information about the workshop is provided below.
International Organisation Committee
Kai Bongs, Philippe Bouyer, Oliver Buchmueller, Benjamin Canuel, Marilù Chiofalo, John Ellis, Naceur Gaaloul, Jason Hogan, Timothy Kovachy, Ernst Rasel, Guglielmo Tino, Wolf von Klitzing, Mingsheng Zhan
Local Organisation Committee
Gianluigi Arduini, Sergio Calatroni, Albert De Roeck, Michael Doser, Elina Fuchs
Atom Interferometry (AI) is a well-established quantum sensor concept based on the superposition and interference of atomic wave packets, which affords exceptionally high sensitivity, e.g., to inertial/gravitational effects. AI experimental designs take advantage of features used by state-of-the-art atomic clocks in combination with established techniques for building inertial sensors.
The experimental landscape of AI projects has expanded significantly in recent years, ranging from ultra-sensitive experimental setups to portable devices and even commercially available gravimeters. Several large-scale terrestrial AIs based on Cold Atom technologies are currently under construction, in planning stages or being proposed.
Five large-scale fully funded prototype projects are currently under construction, namely AION-10 at Oxford with possible 100m sites at Boulby in the UK and at CERN under investigation, a 10m fountain at Stanford & MAGIS-100 at FNAL in the US, MIGA in France, VLBAI at Hannover in Germany and a 10m fountain & ZAIGA in China [1-7]. These will demonstrate the feasibility of AI at macroscopic scales, paving the way for terrestrial km-scale experiments as the next steps.
There are projects to build one or more km-scale detectors, including AION-km at the STFC Boulby facility in the UK , MAGIA-advanced and ELGAR in Europe , MAGIS-km at the Sanford Underground Research facility (SURF) in the US , and advanced ZAIGA in China .
The goal is that by about 2035 at least one km-scale detector will have entered operation. These km-scale experiments would not only be able to explore systematically the mid-frequency band of gravitational waves and probe possible ultralight dark matter but would also demonstrate the readiness of key technologies ahead of a space-based AI mission such as AEDGE .
Scope of the Workshop
The main goals of the workshop will be to develop a Roadmap for the design and technology choices for one or several km-scale detectors to be ready for operation in the mid 2030s, which is supported by the cold atom community and the potential user communities interested in its science goals. This Roadmap will outline technological milestones as well as refine interim and long-term scientific goals.
This event will bring together the cold atom, astrophysics, cosmology, and fundamental physics communities and will build upon the Community Workshop on Cold Atoms in Space held in September 2021 , which reviewed the cold atom experiment landscape for space and established a corresponding Roadmap for cold atoms in space .
 L. Badurina et al., AION: An Atom Interferometer Observatory and Network, JCAP 05 (2020) 011, [arXiv:1911.11755]
 Susannah M. Dickerson et al, Multiaxis Inertial Sensing with Long-Time Point Source Atom Interferometry, Phys. Rev. Lett. 111, 083001 (2013), [arXiv:1305.1700]
 M. Abe et al., Matter-wave Atomic Gradiometer Interferometric Sensor (MAGIS-100), Quantum Sci. Technol. 6 (2021) 4, 044003, [arXiv:2104.02835].
 B. Canuel et al., Exploring gravity with the MIGA large scale atom interferometer, Sci. Rep. 8 (2018), no. 1 14064, [arXiv:1703.02490].
 D. Schlippert et al,” Matter Wave Interferometry for Inertial Sensing and Tests of Fundamental Physics”, Presented at the Eighth Meeting on CPT and Lorentz Symmetry, Bloomington, Indiana, May 12-16, 2019 (2020), [arXiv:1909.08524]
 L. Zhou, Y. Xiong et al. Development of an atom gravimeter and status of the 10-meter atom interferometer for precision gravity measurement. Gen Relativity & Gravitation 43, 1931–1942 (2011).
 M.-S. Zhan et al., ZAIGA: Zhaoshan Long-baseline Atom Interferometer Gravitation Antenna, Int. J. Mod. Phys. D28 (2019) 1940005, [arXiv:1903.09288].
 B. Canuel et al., ELGAR—a European Laboratory for Gravitation and Atom-interferometric
Research, Class. Quant. Grav. 37 (2020), no. 22 225017, [arXiv:1911.03701].
 I. Alonso et al., Cold Atoms in Space: Community Workshop Summary and Proposed Road-Map (2022) [arXiv:2201.07789].