Atomic and electronic structure in collapsed carbon nanotubes evidenced by scanning tunneling microscopy

The electronic behavior of a radially collapsed armchair carbon nanotube encountered by scanning tunneling microscopy experiments is presented in a study that probes the electronic changes directly associated with the atomically resolved structural perturbations. The finite density of states obtained through scanning tunneling spectroscopy at the Fermi energy when the interspacing of the flattened faces does not allow for bond formation suggests that the electronic properties are slightly modified under mild radial deformations and provides a striking verification of previous theoretical predictions and discussions. The study clearly illustrates the challenges to be faced in the contacting of future nanowires, predicted to be the active component in integrated circuits. © 2007 The American Physical Society.