Abstract by: Simona Achilli

Enhanced Magnetic Hybridization of C60 on Fe(001) by a Two-Dimensional Chromium Oxide Layer

Interfaces between ferromagnetic metals and organic semiconductors demonstrated promising spin-dependent properties that make them suitable for applications in spintronics.[1] The detailed characterization of the spinterface and a deep understanding of the hybridization mechanisms that are responsible of the spin polarization are stepping stone to achieve an accurate control of the interface and to design physical systems with tailored properties.

We investigate here, by a joint experimental and theoretical effort, the interface formed by C60, the prototype organic semiconductor, and the Fe(100) surface. We demonstrate, through X-ray Magnetic Circular Dichroism (XMCD), that the inclusion of a thin Chromium oxide layer at the interface enhances the magnetic hybridization between the molecule and the surface,[2] in agreement with the increased hybridization between molecule and substrate states probed by photoemission experiments.

By means of state of the art ab initio calculation we characterize the local interface morphology, the magnetic configuration of the surface and the induced spin dependent electronic properties of the molecule. Moreover, in order to describe the XMCD spectra of carbon we consider the electronic excitation of the interface C atoms from the 1s core state to the Fermi level. We show that the energy dependent spin density on the molecule reflects the magnetic electronic properties of the surface. The theoretical results support the experimental finding and confirm that tailoring the surface electronic and magnetic properties is an effective strategy in order to control the magnetic properties of the spinterface.

References:

[1] Rocha, A. R. et al., Nat. Mater. 4, 335−339 (2005).

[2] A. Brambilla et al., Nano Lett. 17, 7440 (2017).