# Electron collimation at van der Waals domain walls in bilayer graphene

## TL;DR

This paper demonstrates that domain walls between single layer and AA-stacked bilayer graphene can produce highly directional electron beams, controllable with magnetic fields, with potential applications in nanoscale electron optics.

## Contribution

It introduces a novel method of electron beam collimation using domain walls in bilayer graphene, supported by semi-classical and wave dynamics simulations.

## Key findings

- Supports two types of collimated electron beams from AA-BLG cones
- Collimation remains robust with varying layer numbers and edge types
- Magnetic fields can steer the collimated electron beams

## 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.