The miniaturized laser system, developed with major contributions from researchers at Johannes Gutenberg University Mainz
Photo Credit: © Sören Boles
Scientific Frontline: Extended "At a Glance" Summary: Miniaturized Laser Systems for Dual-Species Quantum Gas Mixtures
The Core Concept: Researchers have successfully generated atomic quantum gas mixtures—specifically, Bose-Einstein condensates (BECs) consisting of rubidium and potassium—with an unprecedented particle flux under microgravity conditions. This was made possible by a highly sophisticated, miniaturized laser system that controls and cools the atoms without adding significant mass or payload volume.
Key Distinction/Mechanism: Unlike previous systems that generated a BEC from a single atomic species, this apparatus simultaneously cools and manipulates two different atomic species. It utilizes optical benches made from Zerodur, a glass-ceramic material with an exceptionally low coefficient of thermal expansion, to maintain stability under extreme mechanical stress and temperature fluctuations.
Major Frameworks/Components:
- Bose-Einstein condensates (BECs), an "exotic" state of matter near absolute zero where macroscopic quantum phenomena occur.
- Miniaturized laser modules and optical interfaces designed for extreme space environments.
- Zerodur glass-ceramic optical benches that connect laser modules to the vacuum system.
- Microgravity testing environments, such as the Einstein Elevator.
Branch of Science: Quantum Physics, Optics, and Aerospace Engineering.
Future Application: This technology provides the foundation for future space missions and quantum sensors, such as the planned German-American BECCAL atom laboratory aboard the International Space Station (ISS).
Why It Matters: Enabling robust, high-precision quantum gas experiments in space allows physicists to test the fundamental laws of the universe, including Einstein's equivalence principle, by measuring whether different atomic species experience exactly the same acceleration during free fall.
An international team of researchers has succeeded in producing atomic quantum gas mixtures with an unprecedented particle flux. In the journal Nature Communications, the scientists report on experiments conducted with the MAIUS-B apparatus, in which Bose–Einstein condensates (BECs) consisting of two different atomic species—rubidium and potassium—were generated and studied under microgravity conditions in the Einstein Elevator at Leibniz University Hannover, Germany. A key contribution to this achievement came from a technological development at Johannes Gutenberg University Mainz (JGU): the highly sophisticated and compact optical system used to control the atoms.
Technology as a Key to Success
Bose–Einstein condensates are considered an “exotic” state of matter that exists near absolute zero, where quantum mechanical phenomena become observable on a macroscopic scale. While the generation of a BEC from a single atomic species was first achieved in space during the MAIUS-1 mission in 2017, simultaneously cooling and manipulating two different atomic species presented the researchers with enormous technological challenges.
To meet these challenges, the Mainz research group, led by Professor Patrick Windpassinger and Dr. André Wenzlawski from the Institute of Physics at JGU, developed a miniaturized laser system in collaboration with Humboldt-Universität zu Berlin and the Ferdinand-Braun-Institut, Berlin. Despite requiring twice as many lasers as well as additional optical and electronic components, the system maintained almost the same payload volume and mass. “Our task was to develop the optical interfaces between the laser modules and the vacuum system, which are essential for cooling and manipulating the atoms,” explained Wenzlawski.
A central technological component of the system is the set of optical benches, which form the interface between the laser modules and the vacuum system. These were developed jointly by JGU and the University of Hamburg. The optical benches are based on the glass-ceramic material Zerodur, which is characterized by an exceptionally low coefficient of thermal expansion. “This stability is crucial for maintaining precise control of the atoms under the extreme mechanical loads of a rocket launch and varying temperature conditions,” said Wenzlawski.
The long-term operation of the apparatus in the Einstein Elevator and in laboratory environments has validated the technological concept. The system achieves the highest atomic flux reported to date for such a dual-species BEC mixture, outperforming existing mobile systems by an order of magnitude.
Pioneering Technology for Future Space Missions
The technologies developed in Mainz represent a major milestone in the use of quantum sensors in space. The robustness and precision of the optical modules provide the foundation for future flagship projects, such as the German–American BECCAL atom laboratory aboard the International Space Station (ISS). Systems of this kind will enable scientists to test Einstein’s equivalence principle with unprecedented precision by measuring whether different atomic species experience exactly the same acceleration during free fall.
Funding: German Space Agency at the German Aerospace Center (DLR).
Published in journal: Nature Communications
Title: Apparatus for quantum-mixture research in microgravity
Authors: Baptist Piest, Jonas Böhm, Timothé Estrampes, Priyanka Guggilam, Annie Pichery, Paweł Arciszewski, Wolfgang Bartosch, Sören Boles, Klaus Döringshoff, Michael Elsen, Ortwin Hellmig, Christian Kürbis, Dorthe Leopoldt, Gabriel Müller, Alexandros Papakonstantinou, Christian Reichelt, André Wenzlawski, Thijs Wendrich, Éric Charron, Christoph Lotz, Achim Peters, Klaus Sengstock, Andreas Wicht, Patrick Windpassinger, Jens Grosse, Naceur Gaaloul, and Ernst Maria Rasel
Source/Credit: Johannes Gutenberg-Universität Mainz
Edited by: Scientific Frontline
Reference Number: qs080526_01
