The annual report also presents our recent technical development as well as facts and figures about MGML, our user program and our involvement in international structures.

A key component enabling this research is access to advanced experimental infrastructure provided by the Materials Growth & Measurement Laboratory. The investigation of ultraclean superconductors requires precise control of sample quality and the ability to probe physical properties under extreme conditions, including low temperatures, high magnetic fields, and applied pressure. These capabilities are essential for identifying exotic quantum states such as those potentially hosting Majorana fermions, which are of interest for future quantum technologies. The Junior Star project “STiUS: Symmetry and Topology in Ultraclean Superconductors” will further expand this research, leveraging the open-access environment of MGML to pursue high-impact discoveries. These achievements illustrate how state-of-the-art infrastructure supports both scientific excellence and the development of independent research careers.

A second project guided the student through the full cycle of experimental solid-state research—from crystal growth to advanced characterization. The student prepared single crystals and investigated their structural, magnetic, and thermodynamic properties using techniques such as magnetometry and low-temperature calorimetry, with access to high magnetic fields reaching up to 20 Tesla. By analysing the measured data, the project explored fundamental magnetic behaviour and addressed questions related to exotic quantum states, including the possible presence of a quantum spin liquid. Together, these internships highlight the role of MGML as an open-access research infrastructure that not only supports cutting-edge science but also actively engages and trains the next generation of physicists through direct participation in real research environments.

Organised in the framework of the International Integrated Collaboration Project for ICU & University Academic Alliance in Taiwan (UAAT), the workshop focused on advanced two-dimensional materials and their application in next-generation optoelectronics. Central to this effort is the study of van der Waals heterostructures—atomically engineered systems with significant potential for photonics, quantum technologies, and electronic devices. The meeting highlighted how collaborative research, supported by advanced material characterisation and shared expertise, can drive high-impact discoveries. It also underscored the role of Czech research infrastructures in enabling such work, particularly through their capabilities in materials synthesis, nanofabrication, and comprehensive physical characterization. It also underscored the role of Czech research infrastructures in enabling such work, particularly through their capabilities in materials synthesis, nanofabrication, and comprehensive physical characterization, which form a critical foundation for ongoing and future international projects.

The MPMS3 operates in a cryogenic environment with temperatures ranging from 0.3 K up to 400 K and magnetic fields up to ±7 T, providing a versatile platform for exploring material properties under extreme conditions. Additional capabilities include in-situ light irradiation (UV–visible range), electrical resistivity measurements, and the use of hydrostatic and uniaxial pressure cells for tuning material responses. This acquisition is part of the strategic upgrade of MGML infrastructure supported by the Jan Amos Komenský Operational Programme (2024–2026), aimed at expanding experimental possibilities in areas such as multiferroics, strongly correlated systems, and functional materials. The new system significantly enhances the laboratory’s ability to provide high-quality, open-access research services to both national and international users.

Moiré sliding ferroelectricity is a recently discovered phenomenon in van der Waals materials, where a relative displacement or rotation between weakly bonded layers produces long-range moiré patterns. These patterns, widely known from optical systems, can fundamentally alter the electronic and structural properties of materials when formed at small twist angles. First predicted theoretically and later confirmed experimentally in artificial heterostructures, moiré ferroelectricity provides a pathway toward designing multiferroic systems with unconventional properties, including ferroelectric-like behavior in metallic materials and anomalous piezoelectric responses. Because van der Waals layers—such as those found in graphite or graphene—can be easily stacked and rotated, moiré engineering has become a powerful tool in modern materials science. The realization of this effect in naturally occurring misfit layered compounds significantly broadens its applicability and creates new opportunities for fundamental research and future device concepts.

The initial setup has been continuously optimized, balancing several key parameters—such as accessible sample space diameter versus beam size—to improve the quality of the collected data. The highest pressures reached so far are 23 GPa (UCu₂P₂) and 30 GPa (EuRu₂P₂), with further improvements likely possible through continued optimization and natural ageing of the pressure cell.

These developments have already contributed to multiple student projects, including a Ph.D. thesis (P. Král, 2024), a Bc. thesis (M. Jesenič, 2024), and a student faculty grant (M. Bystrický). Data from these initial experiments have been published or are currently being prepared for publication.

Despite being performed in a laboratory setting rather than at a synchrotron, the data quality is sufficient to observe the pressure dependence of lattice constants, detect pressure-induced structural transitions, and identify signs of pressure-induced valence transitions. These results have already supported successful beamtime proposals at international high-pressure facilities.

The annual report also presents our recent technical development as well as facts and figures about MGML, our user program and our involvement in international structures.

The research focuses on the unconventional superconductor UTe₂, a promising candidate for spin-triplet pairing. Using pulsed magnetic fields up to 70 Tesla, researchers observed that the superconducting critical temperature (T_c) increases to approximately 2.4 K under magnetic fields near 40 Tesla. This finding is counterintuitive, as magnetic fields typically suppress superconductivity; however, in this case, they appear to stabilize and enhance it under specific conditions.

While these extreme conditions are far from practical for technological applications, this work provides critical insights into the unique mechanisms driving superconductivity in UTe₂ and related materials. By advancing our understanding of the interplay between magnetism and superconductivity, this study contributes to the broader effort to unravel the physics of unconventional superconductors.

The high-quality single crystals of UTe₂ used in this study were prepared by Dr. M. Vališka’s team at MGML. For more details, see our previous posts tagged UTe₂.

This large-scale collaboration was made possible through dual access provided by the ISABEL project.