Creating and Manipulating Electron Beams in Graphene
نویسندگان
چکیده
An electron collimator composed of a point-like source and a parabolic pn junction is proposed as a generator of highly focused electron beams in graphene. The collimator is based on negative refraction and Klein collimation, which are unique to pseudo-relativistic Dirac materials. The electron beams generated by the lensing apparatus can be steered by a weak magnetic field without losing collimation, which makes the parabolic lens a flexible platform for next-generation graphene electron optics experiments. This is shown by a few example applications concerning angle-resolved transmission at a pn junction, transverse magnetic focusing, and mapping of the current flow in scanning gate microscopy.
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