Magnetic properties of nanotube structures

摘要

With the discovery of carbon nanotube structures, a new class of materials with a reduced dimensionality has been introduced. Among various forms of carbon nanotubes, the single-walled nanotube has attracted much attention because of its unique structural and electrical properties. In this work, we have considered nanotube models of armchair (2,2) and zigzag (4,0) with one 71 orbital per atom. We have studied the magnetic thermodynamic properties of these models using a single Hubbard model at half-filling. In these calculations we have used the grand canonical quantum Monte Carlo method. Our results show the temperature and field dependence of the magnetic susceptibility, subtracting the diamagnetic contribution, of the considered nanotube models in very good qualitative agreement with the experimental data for a mixture of nanotubes of different diameters. (C) 2004 Elsevier B.V. All rights reserved.