How cold can you get in space? Quantum Physics at cryogenic temperatures in space

TL;DR

This paper examines the potential for passive cooling in space to achieve cryogenic temperatures for quantum experiments, emphasizing the challenges of shielding and heat isolation.

Contribution

It analyzes the limits of passive cooling methods in space for quantum experiments, providing insights applicable to various cryogenic space-based research setups.

Findings

Passive cooling can reach cryogenic temperatures with proper shielding.

Heat exchange with the platform limits achievable temperatures.

Design considerations are crucial for quantum decoherence experiments in space.

Abstract

Although it is often believed that the coldness of space is ideally suited for performing measurements at cryogenic temperatures, this must be regarded with caution for two reasons: Firstly, the sensitive instrument must be completely shielded from the strong solar radiation and therefore, e.g. either be placed inside a satellite or externally on the satellite's shaded side. Secondly, any platform hosting such an experiment in space generally provides an environment close to room temperature for the accommodated equipment. To obtain cryogenic temperatures without active cooling, one must isolate the instrument from radiative and conductive heat exchange with the platform as well as possible. We investigate the limits of this passive cooling method in the context of a recently proposed experiment to observe the decoherence of quantum superpositions of massive objects. The analyses and conclusions are applicable to a host of similar experimental designs requiring a cryogenic environment in space.