Electrical Conductance of a Zig Zag Carbon Nanotube in the Presence of a Few Vacancies Using Recursive Green's Function Method

Abstract

We numerically investigate the electrical conductance of a zigzag carbon nanotube (SWCNT) in the presence of few vacancies, which is attached to two semi-infinite leads. The vacancies are distributed in direction of axis and chiral vector of zigzag SWCNTs. By taking advantage of Green's function method under continuum tight-binding model, we study the electrical conductance and current for fixed length and the vacancy concentration of the center region. It is found that in the both vacancy distributions, the conductance degrades more as the vacancy distance decreases. We also sketch the numerical implementation of these methods and illustrate the metal-semiconductor transition related to the spatial distribution of vacancies. Also, the details of the vacancy distributions are found to profoundly influence the I –V characteristics.