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arXiv · 2012.14963

Switching valley filtered current directions in multi-terminal graphene systems

Vanessa Torres·Daiara Faria·Andrea Latgé
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Abstract

Valley filtering processes have been explored in different graphene-based configurations and scenarios to control transport responses. Here we propose graphene multi-terminal set-ups properly designed to obtain valley filtered currents in a broad range of energy, besides the possibility of controlling their directions. We explore graphene systems with extended mechanical fold-like deformations as an opportunity to enhance valley filtered transmission. The mixing between the electronic confinement effects due to a magnetic field and strain results in a selective drive of the current components in the quantum Hall regime. We adopt the mode-matching method within the Green's function formalism, allowing the direct analysis of the strain effect on each valley transmission. We estimate a threshold map of confinement parameters, characterized by the magnetic, deformation, and set-up lengths, to optimize valley filter transport processes and the proper switch of the valley polarized current directions.

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Vanessa Torres, Daiara Faria, Andrea Latgé. 2020-12-29. Switching valley filtered current directions in multi-terminal graphene systems. https://doi.org/10.1103/physrevb.103.115437

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