Multi-walled nanotubes: Commensurate-incommensurate phase transition and NEMS applications

Interaction of non-rigid walls of double-walled carbon nanotubes is studied within the Frenkel-Kontorova model. It reveals a clearly defined commensurate-incommensurate phase transition. Parameter which determines this phase is calculated for a set of double-walled nanotubes with non-chiral commensurate walls using ab initio interwall interaction energies and elastic properties. Possibility of formation of incommensurability defects in the commensurate phase is considered. The length of the defects and energy of their formation are calculated. Principal scheme of strain nanosensor based on the commensurate-incommensurate phase transition in double-walled nanotube is proposed.