Skip to main content

Magnetic Hybrid Metal-Organic Interfaces

Periodic Reporting for period 1 - MagicFACE (Magnetic Hybrid Metal-Organic Interfaces)

Reporting period: 2019-01-01 to 2020-12-31

Several experimental and theoretical works have suggested organic semiconducting molecules as an excellent and promising alternative for the development of quantum information processing and molecular spintronic based devices. MagicFACE explores new and exotic spin textured interfaces by using as substrate a non-conventional ferromagnetic surface-alloy, which contains rare earths (RE) atoms and noble metals. The broad number of possible RE atoms used for the preparation of such alloys provides an attractive platform to optimize and tune magnetic metal-organic interfaces. In this context MagicFACE aims to study the interaction at the hybrid metal-organic interface combining a wide variety of spectroscopic approaches with three key scientific objectives:
- Demonstration of different hybrid metal-organic interfaces with enhanced magnetic properties prepared on two-dimensional surface alloys with non-conventional ferromagnetism.
- Unravel the effect that the formation of the hybrid metal-organic interface has on the magnetic and electronic properties of both the non-conventional ferromagnetic two-dimensional substrate and organic molecular layer.
- Disentangle the effect of the magnetic coupling between the ferromagnetic substrate and organic molecular layer on the spin-dependent electronic properties at the interface.
The project will have direct and short-term impacts for nanoscience and self-assembly research, and potentially wider and more long-term impacts on development of future effective molecular spintronic-based devices like for example organic spin-valves or spin-organic light emitting diodes (spin-OLEDs).
During this period several non conventional REAu2 alloys have been prepared and analyzed as substrate (GdAu2, HoAu2 and YbAu2, EuAu2) for the further evaporation of different organic molecules. Subsequently, a systematical structural analysis was performed in-situ by several techniques like low energy electron diffraction (LEED) and scanning tunneling microscopy (STM). The next step was the electronic characterization by means photoemission techniques in order to confirm the quality of the REAu2monolayers. As result of this deep analysis a first publication focus on the comparison between the electronic and magnetic properties of these materials was written and finally accepted and published in November 2020.
Moreover, on these surfaces several organic molecules were evaporated in order to check for the electronic and magnetic properties of the hybrid organic interfaces. The first candidate was Cu-phthalocyanine (CuPc) that was evaporated on the REAu2 surfaces commented above, obtaining interesting results that confirm the effect that the different RE atoms play in the electronic properties of the organic interface. The magnetic properties of the different surface compounds and molecules were searched by X-ray magnetic circular dichroism (XMCD) in several beam times realized in synchrotrons like ALBA (Barcelona) and SOLEIL (Paris). Regarding this point, I would like to remark that the access to these international installations is limited in time and only possible after a positive evaluation of the measurement project by a scientific committee. Three different measurement times in synchrotrons were obtained during this period. One in 2019 and two in 2020 after successfully applications to the different competitive calls that the synchrotrons periodically open. Additionally to the work with CuPc other organic molecule with more complexity (TbPc2) was evaporated on the REAu2 surfaces, and also on hexagonal boron nitride monolayers. Concerning the magnetic properties of the organic interfaces it was realized that depending on the RE atom used, the magnetic anisotropy of the system can be modified. At the present, a scientific paper focus on the electronic and magnetic properties of CuPc on different REAu2 surfaces is under preparation. Moreover, other works related with other Pc molecules and the growth of hexagonal boron nitride monolayers were performed during this period in collaboration with scientific colleges of the host institution. From these collaborations, two scientific papers has been written, although they are still under evaluation.
Additionally, during 2019 several dissemination and outreach activities were performed. The results of the scientific investigation were presented in two different international conferences (JEMS in Sweden and Chem-2Dmat in Germany). Outreach activities were performed in San Sebastian with the participation in several events like “Vidas Científicas” (Scientific lifes) where my scientific carrier and actual scientific work as Marie Curie fellow was presented to hundreds of high-school students for the promotion of their scientific vocation. Moreover, I was participating periodically in the high school visiting program organized in the Centro de Física de Materiales of San Sebastian, explaining and showing the regular work in a scientific lab and promoting the work of a woman scientist among high-school female students. Moreover, I would like to comment my participation in the Week of Science in San Sebastian organized by the University of the Basque Country. This event was more focused on a more general public and families. Additionally, a secondment was performed during three months in the company Bihurcrystal, located in San Sebastian. Originally the work was planned based on the optimization and development of the atomic layer injection (ALI) device for the evaporation of complex organic molecules. Unfortunately, due to several technical problems my work in the company was finally focused in the design and development of a vacuum suit case, thought for the transport of samples preserving ultra-high vacuum conditions.
The main progress in this project is the evaluation and study of a new family of REAu2 monolayers for the further preparation of hybrid metal-organic interfaces that display completely different magnetic and electronic properties depending on the RE atom used in the alloy. It is the first time that it is evaluated the effect that the formation of a hybrid metal-organic interface has on the magnetic and electronic properties of both the non-conventional ferromagnetic two-dimensional substrate (REAu2) and organic molecular layer. Moreover, this project examine in detail, for the first time the effect of the electronic state of the substrate on the magnetic properties of the hybrid metal-organic interface. The publication of our results in future scientific reports may induce the use of these or similar compounds in the design of devices like organic spin valves, and moreover a new way to evaluate the type of materials that may be adequate for the development of organic spintronics.
YbAu2 and HoAu2 surface compounds: electronic and magnetic properties