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.
@article{arxiv.cond-mat/0412406,
title = {Zener quantum dot spin filter in a carbon nanotube},
author = {D. Gunlycke and J. H. Jefferson and S. W. D. Bailey and C. J. Lambert and D. G. Pettifor and G. A. D. Briggs},
journal= {arXiv preprint arXiv:cond-mat/0412406},
year = {2007}
}
Comments
8 pages latex, 5 eps figs. Accepted to J. Phys. Cond. Mat