LEMON: large-scale magnetic cooling

On November 19, at the EIC Clean and Efficient Cooling Portfolio meeting, our Sustainability Manager, Harris Mubeen, conducted a workshop on Life Cycle Assessment (LCA). The workshop introduced participants to the fundamental concepts and methodology of LCA, providing a solid foundation for practical application.

The session also included a hands-on exercise, during which portfolio companies developed functional units tailored to their cooling products and technologies, effectively kickstarting their LCA journey.

In addition, an LCA Guide was developed and distributed to the portfolio companies to provide structured support for their ongoing assessments. The workshop created a collaborative environment to explore environmental impacts, exchange best practices, and identify opportunities for more eco-efficient and sustainable cooling solutions.

At the CoolMag conference in Košice, Slovakia, our Cryogenic Engineer Peter Schüßler presented kiutra's latest advances on 'Modeling and scaling of ADR systems for next-generation millikelvin cooling.'

He shared preliminary measurements and outlined the strategy behind the LEMON project, which focuses on developing a scalable, helium-3-free cryogenic cooling solution capable of reaching millikelvin temperatures.

The LEMON project has made significant progress over the past months, advancing in line with the planned project timeline. Particular focus has been placed on Work Package 1, development of the core components. A full-day workshop was held on May 29 to review and reflect the project's first half-year, providing an opportunity to discuss all major topics worked on so far. The session fostered productive exchanges, ensured alignment across the entire team, and helped establish clear tasks and priorities for the next phase. The workshop also played a key role in bringing all contributors up to speed, strengthening overall coordination and cohesion within the project.

Steffen Säubert, our Senior Product Manager, delivered a talk on LEMON's capabilities at the APS Global Physics Summit in Anaheim, California on Friday 21 March.

Talk summary: Large-scale magnetic cooling for quantum computing. As quantum computing advances towards large-scale deployment, achieving ultra-low temperatures efficiently and reliably has become paramount. A promising solution is to scale adiabatic demagnetization refrigeration (ADR), a technique capable of reaching millikelvin temperatures without requiring cryogenic liquids, most notably a technology independent of helium-3.

Our primary objective is to enhance critical ADR components, including mechanical and superconducting (SC) heat switches, magnet and cooling media design as well as the exploration of novel refrigerants. These components are essential to improve cooling performance, both in temperature and cooling power, and ensure scalability.

This presentation covers ongoing research and innovative approaches across these domains, drawing on materials science, thermal management, and SC technology to advance ADR systems. By refining these fundamental technologies, ADR offers a scalable solution, positioning magnetic cooling as a vital platform for the next generation of quantum computing.

A few months into the LEMON project, we are making big steps towards large-scale magnetic cooling. Within work package 1, our team is working on new designs to significantly increase the size (and thus the cooling capacity) of our refrigerant package and to improve the thermal conductivity performance of the mechanical heat switches. To this end, our testing cryostat, which will allow for rapid prototyping, is almost finished and will help us validate our theoretical calculations with experimental data. We have also started working on the overall system architecture, e.g. to also accommodate the new design for large ADR magnets.

It was a great pleasure to host this year's scesamm workshop on strongly correlated electron systems as advanced magnetocaloric materials at kiutra. The event gave us a unique opportunity to introduce the LEMON project to the magnetocaloric research community. Magnetic cooling at cryogenic temperatures is becoming increasingly important for a variety of applications in fundamental science, quantum and industrial technologies. Its performance and adoption can benefit from novel materials with improved properties, such as cooling performance, security of supply, sustainability and manufacturability. It was inspiring to meet some of the experts in this field and to hear their presentations on the theory, synthesis, experimental investigation and application of novel materials for magnetocaloric cooling.

Our CEO, Alexander Regnat, attended the kick-off meeting of the EIC Pathfinder portfolio for clean and efficient cooling in Brussels. He was joined by CTO Jan Spallek and Senior Product Manager Steffen Säubert. During the meeting, they met with teams from other portfolio companies working on innovative cooling technologies. They learned about these projects and explored opportunities for collaboration. The team was warmly welcomed to Brussels by their portfolio project officers, experts and program managers.