Chapter 6 - Nonlinear optical properties of fullerenes and carbon nanotubes

Abstract

This chapter discusses the nonlinear optical (NLO) properties of fullerenes and carbon nanotubes. Nonlinear optics, which focuses mainly on the study of nonlinear optical phenomena that occur as a consequence of the modification of the optical properties of a material owing to the presence of light, plays an important role in many areas of science and technology. The chapter follows standard conventions, where the dimensions of physical quantities are not given explicitly, but instead Gaussian units or electrostatic units (esu) are used to quote values. Based on the laws of quantum mechanics, explicit expressions for the nonlinear optical polarizability of molecules can be calculated. On the basis of the electronic structure obtained in the extended Su–Schrieffer–Heeger (ESSH) model, the second-order hyperpolarizabilities of armchair and zigzag tubular fullerenes can be calculated. The chapter uses the ESSH model to describe fullerenes and carbon nanotubes. However, the model should be modified to include the effect of the dopant ions to describe the substituted tubular fullerenes and carbon nanotubes.