Hybrid molecule/inorganic quantum material interfaces

• Applicants: Professor Dr. Angelo Di Bernardo; Professorin Dr. Elke Scheer
• Subject Area: Experimental Condensed Matter Physics
• Term: since 2025
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 573764948

The fabrication of hybrids consisting of molecules adsorbed onto the surface of other inorganic quantum materials represents an interesting approach to design and study material systems with physical properties and effects that cannot be achieved using alternative methods. The low cost of molecular materials, the large degree of tunability of their physical properties, and their long spin coherence times make them an ideal multifunctional platform for quantum computing and spintronic applications. The deposition of molecules in the form of thin film layers and the formation of hybrid interfaces with other materials, however, usually leads to non-trivial changes compared to the properties of the bare material constituents, which requires a detailed study of these hybrid systems, before any devices based on them can be conceived. Over the past years, molecular/inorganic material hybrids have been the focus of intense research, especially with regards to the properties of one side of the hybrid interface, i.e., the molecular side. This leaves the potential for the discovery of new phenomena in the inorganic side of the hybrid largely unexplored. The lack of comprehensive studies on the inorganic side is mainly due to the current limited access to the experimental techniques available to study the properties of buried interfaces. This project focuses on a class of molecular magnetic materials known as single molecule magnets (SMMs) which act as weakly-interacting isolated quantum spins. We plan to investigate the physics of the interfaces formed between SMMs and other inorganic quantum materials (IQMs), in particular superconductors (Ss). Our project aims at revealing the local magnetic and electronic properties of these novel hybrid material interfaces, also as a function of depth from their interfaces, to gain a deeper understanding of their fundamental properties and realize their potential for future device-based applications. We will investigate the SMM/IQM hybrids using low-energy muon spin rotation spectroscopy (LE-μSR) at the Paul Scherrer Institute, which several groups including ours have already demonstrated to be ideal for the study of the local electronic and magnetic properties of multilayers as a function of depth. This investigation will help us fill in the knowledge gap currently existing in the literature. For those SMM/IQM systems where interesting effects are observed, we will pattern them into nanoscale-size devices at the University of Konstanz, which we will characterize for their low-temperature magnetotransport properties. The complementarity of our approaches and research skills in materials growth, device fabrication and LE-μSR will help shed light onto the intriguing physics of SMM/IQM hybrids and set the basis for their future applications in spintronics and emerging quantum technologies.

• DFG Programme: Research Grants
• International Connection: Norway, Switzerland, USA
• Partner Organisation: Schweizerischer Nationalfonds (SNF)
• Cooperation Partners: Dr. Matthew Brahlek; Professor Dr. Jacob Linder; Dr. Zaher Salman