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arXiv · 1904.06403

Electrically addressing the spin of a magnetic porphyrin through covalently connected graphene electrodes

Jingcheng Li·Niklas Friedrich·Nestor Merino·Dimas G. de Oteyza·Diego Peña·David Jacob·Jose Ignacio Pascual
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Abstract

We report on the fabrication and transport characterization of atomically-precise single molecule devices consisting of a magnetic porphyrin covalently wired by graphene nanoribbon electrodes. The tip of a scanning tunneling microscope was utilized to contact the end of a GNR-porphyrin-GNR hybrid system and create a molecular bridge between tip and sample for transport measurements. Electrons tunneling through the suspended molecular heterostructure excited the spin multiplet of the magnetic porphyrin. The detachment of certain spin-centers from the surface shifted their spin-carrying orbitals away from an on-surface mixed-valence configuration, recovering its original spin state. The existence of spin-polarized resonances in the free-standing systems and their electrical addressability is the fundamental step for utilization of carbon-based materials as functional molecular spintronics systems.

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Jingcheng Li, Niklas Friedrich, Nestor Merino, Dimas G. de Oteyza, Diego Peña, David Jacob, Jose Ignacio Pascual. 2019-04-12. Electrically addressing the spin of a magnetic porphyrin through covalently connected graphene electrodes. https://doi.org/10.1021/acs.nanolett.9b00883

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