On surface spin tuning in single molecule magnets

• Applicant: Professor Dr. Mikhail Fonin
• Subject Area: Experimental Condensed Matter Physics
• Term: from 2019 to 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 426218470

Controlled manipulation of the spin states of individual molecules is one of the ultimate goals in materials science and the development of novel electronic devices at the nanoscale. Molecule-based spintronic units promise to possess fundamentally new properties and also offer the advantages of cost-effective fabrication through self-assembly as well as through tailoring fundamental properties by chemical synthesis. Molecular nanomagnets, representing mesoscopic systems with magnetic bistability and versatile quantum behavior, are of particular interest for applications in the fields of spin-based data storage and quantum computation. The main idea of this project is to investigate the structural, electronic and magnetic properties of individual single molecule magnet (SMM) complexes at surfaces as well as to controllably manipulate their fundamental properties by either chemical doping with electron donors and acceptors or by external electric fields using a back-gate electrode within the STM geometry. A special focus is put on the possibility to controllably tune the magnetic properties of SMMs. Despite the recent progress in the synthesis and surface deposition of SMMs, the factors controlling magnetic bistability of SMMs on surfaces remain still unclear. This is in part due to the limited number of SMMs robust enough to withstand the surface deposition as well as due to the absence of reliable protocols which allow for controllable tuning of electronic properties and magnetism of SMMs on surfaces. In the frame of this project, we implement a unique combination of deposition methods and investigation techniques aiming to close this gap and to reveal detailed insight in electronic states and spin properties of well-defined adsorbed single molecular magnets on functional substrates as well as to tune their electronic properties to controllably modify their magnetic behavior. The ultimate goal will be to use submolecular resolution and gating-possibilities within the STM junction in order to tune the electronic and magnetic properties of an individual SMM complex which will provide a deeper insight into the behavior of molecular nanomagnets in realistic electronic devices.

• DFG Programme: Research Grants