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Electron supercollimation in graphene and Dirac fermion materials using one-dimensional disorder potentials

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 نشر من قبل SangKook Choi
 تاريخ النشر 2014
  مجال البحث فيزياء
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Electron supercollimation, in which a wavepacket is guided to move undistorted along a selected direction, is a highly desirable property that has yet been realized experimentally. Disorder in general is expected to inhibit supercollimation. Here, we report a counter-intuitive phenomenon of electron supercollimation by disorder in graphene and related Dirac fermion materials. We show that one can use one-dimensional disorder potentials to control electron wavepacket transport. This is distinct from known systems where an electron wavepacket would be further spread by disorder and hindered in the potential fluctuating direction. The predicted phenomenon has significant implications in the understanding and applications of electron transport in Dirac fermion materials.

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