SPINteger – Molecular-based interfaces supporting integer SPIN transfer.

• Applicants: Professor Dr. Mirko Cinchetti; Dr. Vitaliy Feyer; Dr. Giovanni Zamborlini, Ph.D.
• Subject Area: Experimental Condensed Matter Physics
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 513136560

Creating electronic devices with extraordinary performances, capable of performing billions of logical operations every second with a negligible power consumption has become an imperative in our contemporary society, which is based on information technology. To sustain this technological development, novel materials, beyond silicon-based semiconductors, will be needed and, in this perspective, π-conjugated organic films are one of the most suitable candidates to replace inorganic semiconductors. In this context, novel molecular multi-spinterfaces could be engineered to achieve multifunctionality in a low-dimensional system, offering a way to engineer devices capable of storing quantum information using the molecular spin state. Recently, it has been shown that the large changes in work function (WF) induced by a dielectric layer can modify the electron energy level alignment for molecular adsorbates, promoting charge transfer via tunneling. Since the fractional charge transfer is hindered due to the lack of hybridization, only integer charge transfer is expected to be possible. While this has already been achieved by employing a prototypical dielectric material, such as an ultrathin magnesium oxide (MgO) film, epitaxially grown on the silver (100) surface, SPINteger aims to extend this approach to a truly spinterfaces implemented in tri-layer configuration consisting of an iron substrate magnetically coupled to a molecular system through a MgO thin layer. The main goal of SPINteger is to characterize and control the electron and hole dynamics in this novel Fe/MgO/M molecular multi-spinterfaces supporting spin-polarized integer interface charge transfer. To this end, a state-of-the-art multidisciplinary approach combining synchrotron-based techniques and femtosecond XUV light sources will be used. In particular, combining angle-resolved photoemission spectroscopy and density functional theory calculations provides one of the most advanced methods for band structure characterization: photoemission tomography (PT). We will extend PT to the spin and time domains, by performing spin-resolved experiments in large momentum space regions with both synchrotron and fs-XUV radiation, gaining information on the occupied and unoccupied molecular states, as well as their dynamic. Integer charge transfer implies the possibility to create well-defined molecular spin state as a quantum of information opening the way to the development of novel concepts for data storage, quantum computing and magnetic sensing applications based on magnetically coupled single molecular spins.

• DFG Programme: Research Grants