Coherent Tunneling Through Quantum Wire Tailored by Gaussian Profile

Hassan S. Ashour

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DOI: 10.4236/jmp.2011.23019                

Abstract

In this paper, we propose a novel structure of quantum waveguide. In this structure we tailored the quantum wire by Gaussian Profile. Thus, the Dirac-Delta function potentials are weighted according to Gaussian distribution function. We studied the electronic transmission properties through this tailored quantum waveguide structure. We have assumed that single free-electron channel is incident on the structure and the scattering of electrons is solely from the geometric nature of the problem. We have used the transfer matrix method to study the electron transmission. Coherent Tunneling is achieved through this structure, which is well-defined allowed conduction bands. The electronic conductance spectrum depends on the number of the Dirac delta function potential in the quantum wire. When the number of Dirac delta function potentials in the structure and their strengths are increased, both well defined conductance bands and sharper and narrower forbidden bands are formed. This novel structure has a good defect tolerance. The structure tolerates strength defect and tolerates position defect for the central Dirac delta function in the Gaussian distribution.

Keywords

Mesoscopic Systems, Quantum Waveguide, Quantum Wire

Conflicts of Interest

The authors declare no conflicts of interest.

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