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Zener quantum dot spin filter in a carbon nanotube

D. Gunlycke·J. H. Jefferson·S. W. D. Bailey·C. J. Lambert·D. G. Pettifor·G. A. D. Briggs
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Abstract

We predict and analyze a novel spin filter in semiconducting carbon nanotubes. By using local electrostatic gates, the conduction and valence bands can be modulated to form a double-barrier structure. The confined region below the valence band defines a Zener quantum dot, which exhibits resonant tunneling. The resonances split in a magnetic field to make a bipolar spin filter for applications in spintronics and quantum information processing. We model this using k*p envelope function theory and show that this is in excellent agreement with a corresponding tight-binding calculation.

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D. Gunlycke, J. H. Jefferson, S. W. D. Bailey, C. J. Lambert, D. G. Pettifor, G. A. D. Briggs. 2006-02-02. Zener quantum dot spin filter in a carbon nanotube. https://doi.org/10.1088/0953-8984%2F18%2F21%2Fs10

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