Capillary and van der Waals forces cause nanotubes to deform or even collapse under metal contacts. Using ab initio band structure calculations, we find that these deformations reduce the band gap by as much as 30%, while fully collapsed nanotubes become metallic. Moreover, degeneracy lifting due to the broken axial symmetry, and wave functions mismatch between the fully collapsed and the round portions of a CNT, lead to a 3 times higher contact resistance. The latter we demonstrate by contact resistance calculations within the tight-binding approach.

中文翻译：

---

金属接触变形的碳纳米管的能带结构和接触电阻

毛细管力和范德华力导致纳米管在金属接触下变形甚至塌陷。使用从头算的能带结构计算，我们发现这些变形将带隙减小了多达30％，而完全塌陷的纳米管变成了金属。此外，由于破坏了轴向对称性而引起的简并性提升，以及完全塌陷的碳纳米管和圆形碳纳米管之间的波函数失配，导致接触电阻提高了3倍。我们通过紧密结合方法中的接触电阻计算来证明后者。