ANALYSIS OF QUANTUM CONDUCTANCE OF CARBON NANOTUBE JUNCTIONS BY THE EFFECTIVE-MASS APPROXIMATION

The electron transport through the nanotube junctions that connect dif ferent metallic nanotubes by a pair consisting of a pentagonal defect and a heptagonal defect is investigated with Landauer's formula and th e effective-mass approximation. From our previous calculations based o n the tight-binding model, it is known that the conductance is determi ned almost only by two parameters, i.e., the energy units of the onset energy of more than two channels and the ratio of the radii of the tw o nanotubes. The conductance is calculated again with effective-mass t heory in this paper and a simple analytical form of the conductance is obtained by considering special boundary conditions of the envelope w ave functions. The two scaling parameters appear naturally in this tre atment. The results obtained by this formula coincide fairly well with those of the tight binding model. The physical origin of the scaling law is clarified by this approach. [S0163-1829(98)06431-5].