Regensburg 2019 – wissenschaftliches Programm
MA 2.13: Vortrag
Montag, 1. April 2019, 12:45–13:00, H37
Long-distance ultrafast spin transfer processes through carbon chain structure — •Jing Liu1, Georgios Lefkidis1, Wolfgang Hübner1, and Chun Li2 — 1Department of Physics and Research Center OPTIMAS, Technische Universität Kaiserslautern, Kaiserslautern, Germany — 2Northwestern Polytechnical University, Xi’an, China
Ultrafast spin flip and transfer processes between near magnetic centers have already been theoretically demonstrated on various realistic, or even synthesized molecular systems . Motivated by the delicate spin interaction between the encapsulated magnetic atoms and the atoms of the cage of endohedral fullerenes [2,3] as well as the calculability of such large structures with high precision quantum chemical methods, we use C atoms as spin channels to optically transfer the spin over distances comparable to the actual CMOS scale.
First we transfer the spin across a finite 2D graphene sheet, on which we induce spin localization by attaching two Ni atoms on opposite sites. However, our to-date record distance of 4.428 nm is achieved over a 40-atom-long zig-zag carbon chain, again with two Ni attached. The spins of the two Ni atoms couple due the combination of local and global symmetry, with the nonlinear geometry of the chain (which gives rise to what we term dynamical Goodenough-Kanamori rules). The processes typically finish within 600 fs.
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 C. Li, et al., Carbon 87, 153 (2015).
 C. Li, et al., Phys. Chem. Chem. Phys. 19, 673 (2017).