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arXiv · 2010.14012

Spin-dependent Tunneling Barriers in CoPc/VSe2 from Many-Body Interactions

Runrun Xu·Fengyuan Xuan·Su Ying Quek
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Abstract

Mixed-dimensional magnetic heterostructures are intriguing, newly available platforms to explore quantum physics and its applications. Using state-of-the-art many-body perturbation theory, we predict the energy level alignment for a self-assembled monolayer of cobalt phthalocyanine (CoPc) molecules on magnetic VSe 2 monolayers. The predicted projected density of states on CoPc agrees with experimental scanning tunneling spectra. Consistent with experiment, we predict a shoulder in the unoccupied region of the spectra that is absent from mean-field calculations. Unlike the nearly spin-degenerate gas phase frontier molecular orbitals, the tunneling barriers at the interface are spin-dependent, a finding of interest for quantum information and spintronics applications. Both the experimentally observed shoulder and the predicted spin-dependent tunneling barriers originate from many-body interactions in the interface-hybridized states. Our results showcase the intricate many-body physics that governs the properties of these mixed-dimensional magnetic heterostructures, and suggests the possibility of manipulating the spin-dependent tunneling barriers through modifications of interface coupling.

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Runrun Xu, Fengyuan Xuan, Su Ying Quek. 2020-10-27. Spin-dependent Tunneling Barriers in CoPc/VSe2 from Many-Body Interactions. https://doi.org/10.1021/acs.jpclett.0c02944

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