The effect of magnetic behavior of vacancy defect on the conductance of carbon nanotubes

The influence of vacancy defects on the electric conduction of single-wall carbon nanotubes is studied by use of the Landauer formalism within the coherent regime. The method is based on the single-band tight-binding Hamiltonian, surface Green’s function calculation and the iterative procedure for the transfer matrix. To study the magnetic properties of the vacancies, the mean-field Hubbard model has been used. Including the vacancy defects in the channel region of the device will cause scattering of electrons and reduction of the electron transmission and hence, the current-voltage characteristics. In addition, the current is a little spin-polarized due to the magnetic behaviour of the vacancies.

Keywords:

Single-wall carbon nanotubes , Vacancy , Transfer matrix , Spin-dependent transport