Symmetry-selected spin-split hybrid states inC60/ferromagneticinterfaces

Abstract

. (2016). Symmetryselected spin-split hybrid states in C-60/ferromagnetic interfaces. Physical Review B, 93(8) The understanding of orbital hybridization and spin polarization at the organic-ferromagnetic interface is essential in the search for efficient hybrid spintronic devices. Here, using first-principles calculations, we report a systematic study of spin-split hybrid states of C 60 deposited on various ferromagnetic surfaces: bcc-Cr(001), bccFe(001), bcc-Co(001), fcc-Co(001), and hcp-Co(0001). We show that the adsorption geometry of the molecule with respect to the surface crystallographic orientation of the magnetic substrate as well as the strength of the interaction play a crucial role in the spin polarization of the hybrid orbitals. We find that a large spin polarization in vacuum above the buckyball can only be achieved if the molecule is adsorbed upon a bcc-(001) surface by its pentagonal ring. Therefore, bcc-Cr(001), bcc-Fe(001), and bcc-Co(001) are the optimal candidates. Spin-polarized scanning tunneling spectroscopy measurements on single C 60 adsorbed on Cr(001) and Co/Pt(111) also confirm that the symmetry both of the substrate and of the molecular conformation has a strong influence on the induced spin polarization. Our finding may give valuable insights for further engineering of spin filtering devices through single molecular orbitals.

Observation of a Metastable Honeycomb Arrangement of C60 on Ni(111) with (7 × 7) Periodicity: Tailoring an Interface for Organic Spintronics

“…In this respect, we remark that recent calculations have definitely highlighted the fact that the structural and electronic details of the molecular adsorption onto a magnetic substrate have a central role in defining the spin polarization of the interface states and thus, in perspective, a potential device performance. 45 , 46 …”

Experimental and theoretical investigations of magnetic anisotropy and magnetic hardening at molecule/ferromagnet interfaces

“…It makes C 60 /Co/Pt a good candidate for high perpendicular magnetic anisotropy ultrathin films, with rather large coercive fields. From a more fundamental perspective, it shows that details of the interface matter, which has been recently pointed out for another important property of such interfaces, namely the induced spin polarization of C 60 molecules adsorbed on different magnetic substrates [37]. In the following, we explore by means of tight-binding and density functional theory calculations the impact of different parameters like the Co stacking, the molecular adsorption geometry, and the strain in the Co layer on the induced interfacial magnetic anisotropy.…”

Activating the molecular spinterface

“…DFT has played a key role in casting light on the microscopic origin of the magnetic changes occurring in the inorganic materials 68 ) to the interface plane, or on charge-transfer effects affecting the electronic carrier density at the interface 70,71 . A detailed description of DFT calculations is beyond the scope of this paper, but readers can rely on some recent excellent reviews 34,72 .…”