  AFM manipulation was used to controllably stretch individual metallic
single-walled carbon nanotubes (SWNTs). We have found that SWNTs can sustain
elongations as great as 30% without breaking. Scanned gate microscopy and
transport measurements were used to probe the effects of the mechanical strain
on the SWNT electronic properties, which revealed a strain-induced increase in
intra-tube electronic scattering above a threshold strain of ~5-10%. These
findings are consistent with theoretical calculations predicting the onset of
plastic deformation and defect formation in carbon nanotubes.
