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arXiv · 0911.4017

Dirac electrons in a Kronig-Penney potential: dispersion relation and transmission periodic in the strength of the barriers

M. Barbier·P. Vasilopoulos·F. M. Peeters
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Abstract

The transmission T and conductance G through one or multiple one-dimensional, delta-function barriers of two-dimensional fermions with a linear energy spectrum are studied. T and G are periodic functions of the strength P of the delta-function barrier V(x,y) / hbar v_F = P delta(x). The dispersion relation of a Kronig-Penney (KP) model of a superlattice is also a periodic function of P and causes collimation of an incident electron beam for P = 2 pi n and n integer. For a KP superlattice with alternating sign of the height of the barriers the Dirac point becomes a Dirac line for P = (n + 1/2) pi.

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M. Barbier, P. Vasilopoulos, F. M. Peeters. 2009-11-20. Dirac electrons in a Kronig-Penney potential: dispersion relation and transmission periodic in the strength of the barriers. https://doi.org/10.1103/physrevb.80.205415

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