EXC 2147:  Complexity and Topology in Quantum Matter (CT.QMAT)

• Subject Area: Condensed Matter Physics ; Chemical Solid State and Surface Research ; Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: since 2019
• Website: Homepage
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 390858490

New materials with tailored functionalities are of paramount importance for all modern technologies, from information processing to sustainable energy and health care. In the 21st century condensed-matter physics, as the relevant scientific discipline, has made the revolutionary discovery that the mathematical concept of topology is a fundamental key for the understanding of quantum-mechanical states of matter. This insight has sparked a scientific boom worldwide, leading to the discovery of many new topological quantum materials and their remarkable physical properties, with key contributions from Würzburg (observation of the quantum spin Hall effect) and Dresden (prediction of magnetic monopoles in spin ice). Yet, the field is still in its infancy and, therefore, we propose the excellence cluster "Complexity and Topology in Quantum Matter (ct.qmat)" as a unique research platform for comprehensive studies of the fundamental physics of topological quantum materials and their vast application potential.The cluster unites physicists, chemists, and material scientists in their efforts to understand, control, and apply these fundamentally new states of quantum matter. Based on the strong and complementary scientific expertise and infrastructure in Würzburg and Dresden, ct.qmat will span a broad research program – ranging from materials synthesis via experimental and theoretical studies of novel topological phenomena and their functional control to the design and test of application-relevant device concepts. To this end, the cluster is structured into four Research Areas, with the first three focusing on the role of topology and complexity in different physical settings, namely (A) charge transport, (B) magnetism, and (C) light-matter interaction. Area (D) is devoted to the overarching objective of deriving functionalities from topological phenomena and exploring their application potential for, e.g., loss-less electronics or quantum computing. These activities are based on and will extend the manifold research collaborations between both universities and their partner institutions. Structural elements of the cluster comprise additional professorships and junior research groups, intended to strengthen the expertise within the Research Areas and building scientific bridges between them, as well as the establishment and joint use of complementary research infrastructures. Further central cluster components are the structured support and promotion of young researchers at all qualification levels from PhD students to early career investigators, and the advancement of equal opportunity and diversity in science. Taking advantage of the synergies resulting from the collaboration of both universities, the cluster will thus facilitate excellent training and working conditions. Attracting the best students and scientists will be decisive for the central strategic goal of ct.qmat, namely to become a leading international hub for quantum matter research.

• DFG Programme: Clusters of Excellence (ExStra)
• Applicant Institution: Julius-Maximilians-Universität Würzburg
• Co-Applicant Institution: Technische Universität Dresden
• Participating Institution: Bayerisches Zentrum für Angewandte Energieforschung e.V. (ZAE Bayern); Helmholtz-Zentrum Dresden-Rossendorf (HZDR) ; Hochfeld-Magnetlabor Dresden; Leibniz-Institut für Festkörper- und Werkstoffforschung Dresden (IFW) e.V.; Max-Planck-Institut für Chemische Physik fester Stoffe; Max-Planck-Institut für Physik komplexer Systeme
• Spokespersons: Professor Dr. Ralph Claessen; Professor Dr. Matthias Vojta
• Participating Researchers: Professor Dr. Fakher Fakhry Assaad; Professor Dr. Matthias Bode; Professor Dr. Jeroen van den Brink; Professor Dr. Bernd Büchner; Professor Dr. Vladimir Dyakonov; Professor Dr. Lukas M. Eng; Professorin Dr. Johanna Erdmenger; Professorin Dr. Claudia Felser; Professor Dr. Jochen Geck; Professor Dr. Sebastian Gönnenwein; Professorin Dr. Ewelina M. Hankiewicz; Professor Dr. Sven Höfling; Professor Dr. Dmytro Inosov; Professor Dr. Karl Leo; Professor Dr. Roderich Moessner; Professor Dr. Laurens W. Molenkamp; Professor Dr. Friedrich Reinert; Professor Dr. Michael Ruck; Professor Dr. Giorgio Sangiovanni; Professor Dr. Oliver G. Schmidt; Professor Dr. Ronny Thomale; Professor Dr. Björn Trauzettel; Professor Dr. Joachim Wosnitza