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arXiv · 2409.04815

Carbon nanotube as quantum point contact valley-filter and valley-splitter

Naif Hadadi·Adel Belayadi·Ousmane Ly·Adel Abbout
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Abstract

The electrical characteristics of a carbon nanotube can be significantly modified by applying elastic strain. This study focuses on exploring this phenomenon in a single-walled carbon nanotube (SWNT) using tight-binding transport calculations. The results indicate that, under specific strains, an armchair SWNT can act as a filter, separating the two valley electrons K and Kp. Notably, when subjected to deformation, the SWNT exhibits intriguing behaviors, including a quantized conductance profile that varies with the strength of the strain. Consequently, precise control of the width of the quantized plateaus allows for the generation of a polarized valley current. Furthermore, when both K-types are conducted, the strain is demonstrated to completely separate them, directing each K-type through a distinct pathway.

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Naif Hadadi, Adel Belayadi, Ousmane Ly, Adel Abbout. 2024-09-07. Carbon nanotube as quantum point contact valley-filter and valley-splitter. https://arxiv.org/abs/2409.04815

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