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arXiv · 1407.8048

Quantum transport through 3D Dirac materials

M. Salehi·S. A. Jafari
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Abstract

Bismuth and its alloys provide a paradigm to realize three dimensional materials whose low-energy effective theory is given by Dirac equation in 3+1 dimensions. We study the quantum transport properties of three dimensional Dirac materials within the framework of Landauer-B\"uttiker formalism. Charge carriers in normal metal satisfying the Schr\"odinger equation, can be split into four-component with appropriate matching conditions at the boundary with the three dimensional Dirac material (3DDM). We calculate the conductance and the Fano factor of an interface separating 3DDM from a normal metal, as well as the conductance through a slab of 3DDM. Under certain circumstances the 3DDM appears transparent to electrons hitting the 3DDM. We find that electrons hitting the metal-3DDM interface from metallic side can enter 3DDM in a reversed spin state as soon as their angle of incidence deviates from the the direction perpendicular to interface. However the presence of a second interface completely cancels this effect.

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M. Salehi, S. A. Jafari. 2014-07-30. Quantum transport through 3D Dirac materials. https://doi.org/10.1016/j.aop.2015.04.007

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