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arXiv · 1801.04294

Bandstructure and Contact Resistance of Carbon Nanotubes Deformed by the Metal Contact

Roohollah Hafizi·Jerry Tersoff·Vasili Perebeinos
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Abstract

Capillary and van der Waals forces cause nanotubes to deform or even collapse under metal contacts. Using ab-initio bandstructure calculations, we find that these deformations reduce the bandgap by as much as 30\%, while fully collapsed nanotubes become metallic. Moreover degeneracy lifting, due to the broken axial symmetry and wavefunctions mismatch between the fully collapsed and the round portions of a CNT, leads to a three times higher contact resistance. The latter we demonstrate by contact resistance calculations within the tight-binding approach.

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Roohollah Hafizi, Jerry Tersoff, Vasili Perebeinos. 2018-01-12. Bandstructure and Contact Resistance of Carbon Nanotubes Deformed by the Metal Contact. https://doi.org/10.1103/physrevlett.119.207701

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