Cold atoms physics in space

Wolfgang P. Schleich

Xuzong Chen

The current development of cold atomic physics in space is introduced,with its characteristics and advantage in the microgravity environment discussed.Cold atom samples in space provide unprecedented and powerful tools for atomic physics and precision measurements.Important scientific experiments in the field of cold atomic physics,such as quantum simulation,new matter states,and test of fundamental physical laws,as well as high-tech application exploration in space,are briefly discussed.

Wolfgang A. Ertmer, Ernst Maria Rasel, Ch Salomon +3 more

Wei Ren, Tang Li, Qiuzhi Qu +5 more

Atomic clocks with cold atoms play important roles in the field of fundamental physics as well as primary frequency standards. Operating such cold atom clocks in space paves the way for further exploration in fundamental physics, for example dark matter and general relativity. We developed a space cold atom clock (SCAC), which was launched into orbit with the Space Lab TG-2 in 2016. Before it deorbited with TG-2 in 2019, the SCAC had been working continuously for almost 3 years. During the period in orbit, many scientific experiments and engineering tests were performed. In this article, we summarize the principle, development and in-orbit results. These works provide the basis for construction of a space-borne time-frequency system in deep space.

Siminda 思敏达 Deng 邓, Wei 伟 Ren 任, Jingfeng Xiang +9 more

Abstract This article proposes a new physics package to enhance the frequency stability of the space cold atom clock with the advantages of a microgravity environment. Clock working processes, including atom cooling, atomic state preparation, microwave interrogation, and transition probability detection, are integrated into the cylindrical microwave cavity to achieve a high-performance and compact physics package for the space cold atom clock. We present the detailed design and ground-test results of the cold atom clock physics package in this article, which demonstrates a frequency stability of 1.2 × 10−12 τ −1/2 with a Ramsey linewidth of 12.5 Hz, and a better performance is predicted with a 1 Hz or a narrower Ramsey linewidth in microgravity environment. The miniaturized cold atom clock based on intracavity cooling has great potential for achieving space high-precision time-frequency reference in the future.

Lucas Madeira, Vanderlei Salvador Bagnato