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arXiv · 1907.06827

Electron collimation at van der Waals domain walls in bilayer graphene

Hasan M. Abdullah·D. R. da Costa·H. Bahlouli·A. Chaves·F. M. Peeters·Ben Van Duppen
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Abstract

We show that a domain wall separating single layer graphene (SLG) and AA-stacked bilayer graphene (AA-BLG) can be used to generate highly collimated electron beams which can be steered by a magnetic field. Such system exists in two distinct configurations, namely, locally delaminated AA-BLG and terminated AA-BLG whose terminal edge-type can be either zigzag or armchair. We investigate the electron scattering using semi-classical dynamics and verify the results independently with wave-packed dynamics simulations. We find that the proposed system supports two distinct types of collimated beams that correspond to the lower and upper cones in AA-BLG. Our computational results also reveal that collimation is robust against the number of layers connected to AA-BLG and terminal edges.

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Hasan M. Abdullah, D. R. da Costa, H. Bahlouli, A. Chaves, F. M. Peeters, Ben Van Duppen. 2019-07-16. Electron collimation at van der Waals domain walls in bilayer graphene. https://doi.org/10.1103/physrevb.100.045137

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