Controlling spin polarization of gapless states in defected trilayer graphene with a gate voltage

Wlodzimierz Jaskolski

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arXiv · 2309.16547

Controlling spin polarization of gapless states in defected trilayer graphene with a gate voltage

Wlodzimierz Jaskolski

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Abstract

Trilayer graphene exhibits valley-protected gapless states when the stacking order changes from ABC to CBA and a gate voltage is applied to outer layers. Some of these states survive strong distortions of the trilayer. For example, they persist when the outer layers are partially devoid yielding a system of two trilayers of different stacking order connected by a strip of a single graphene layer. Here we investigate how these states respond to another perturbation, i.e., the presence of magnetic defects, which we model as pi-vacancies. We show that the gap states hybridize with the defect states and strongly spin-split. More importantly, it is demonstrated that by changing the gate voltage value one can change the spin density of the gap states and the corresponding currents at the Fermi level.

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Wlodzimierz Jaskolski. 2023-09-28. Controlling spin polarization of gapless states in defected trilayer graphene with a gate voltage. https://arxiv.org/abs/2309.16547

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