Interferometry of Atomic Matter Waves in the Cold Atom Lab onboard the International Space Station

TL;DR

This paper reports on space-based atom interferometry experiments using ultracold atoms aboard the ISS, demonstrating advanced quantum sensing techniques and measuring photon recoil in microgravity.

Contribution

It presents the first use of matter-wave interferometry in space with ultracold atoms, including an upgraded CAL system and novel measurement demonstrations.

Findings

Successful implementation of a three-pulse Mach-Zehnder interferometer in space

Observation of interference patterns over 150 ms free-expansion time

First measurement of photon recoil using space-based matter-wave interferometry

Abstract

Ultracold atomic gases hold unique promise for space science by capitalizing on quantum advantages and extended freefall, afforded in a microgravity environment, to enable next-generation precision sensors. Atom interferometers are a class of quantum sensors which can use freely falling gases of atoms cooled to sub-photon-recoil temperatures to provide unprecedented sensitivities to accelerations, rotations, and gravitational forces, and are currently being developed for space-based applications in gravitational, earth, and planetary sciences, as well as to search for subtle forces that could signify physics beyond General Relativity and the Standard Model. NASA's Cold Atom Lab (CAL) operates onboard the International Space Station as a multi-user facility for studies of ultracold atoms and to mature quantum technologies, including atom interferometry, in persistent microgravity. In this paper, we report on path-finding experiments utilizing ultracold $^{87}$Rb atoms in the CAL atom interferometer, which was enabled by an on-orbit upgrade of the CAL science module: A three-pulse Mach-Zehnder interferometer was studied to understand limitations from the influence of ISS vibrations. Additionally, Ramsey shear-wave interferometry was used to manifest interference patterns in a single run that were observable for over 150 ms free-expansion time. Finally, the CAL atom interferometer was used to remotely measure the photon recoil from the atom interferometer laser as a demonstration of the first quantum sensor using matter-wave interferometry in space.