Abstract
We present a density functional theory study of the electronic structure, quantum transport and mechanical properties of recently synthesized phosphorus (P) and phosphorus-nitrogen (PN) doped single-walled carbon nanotubes. The results demonstrate that substitutional P and PN doping creates localized electronic states that modify the electron transport properties by acting as scattering centers. For low doping concentrations (1 doping site per ~200 atoms), the quantum conductance for metallic nanotubes is found to be only slightly reduced. The substitutional doping also alters the mechanical
strength, leading to a 50% reduction in the elongation upon fracture, while Young�s modulus remains
approximately unchanged. Overall, the PN- and P-doped nanotubes display promising properties for
components in composite materials and, in particular, for fast response and ultra sensitive sensors
operating at the molecular level.
