Symmetry Based Approach to the Evaluation of Second Order NLO Properties of Carbon Nanotubes

Abstract

This chapter presents a review of the direct implantation of symmetry into calculations of carbon nanotubes (CNTs) second order nonlinear optical properties (NLO). Emphasis is given to potentiality of the method to estimate quantitatively the magnitude of first hyperpolarizability for several CNTs topologies. The main advantage of performing calculations with symmetrized eigenfunctions, relies on the direct identification of the state-to-state transitions contributing to the hyperpolarizability. An estimated value of β ∼ 10-30esu for the non-resonant hyperpolarizability of chiral CNTs is obtained.