The optical properties of metamaterial waveguide structures

Abstract

Metamaterials, artificially engineered structures with negative average relative permittivity and permeability, provide a route to creating potential devices with exciting electromagnetic properties that cannot be obtained with natural materials. One particularly interesting metamaterial device, is a planar metamaterial waveguide structure (MWS) that has potentially exciting applications. In this thesis, the properties and potential applications of metamaterial waveguide structures are explored. In particular, we examine the properties of metamaterial waveguides when the limitations arise from fabrication techniques and physical principles are taken into account. First, we study the basic properties of dispersion curves of an idealized (without loss and dispersion) metamaterial waveguide structure. We show that there are a rich variety of modes, such as the bound modes, the surface polariton modes, and the complex leaky modes, that are supported in MWS and have entirely different properties than the modes of a conventional waveguide structure. These novel modes provide more control over the electromagnetic fields and consequently lead to potential applications ranging from waveguide miniaturization to the slowing down of the light. Next, we study the effects of dispersion and loss, which are the inherent features of metamaterials, on the properties of MWS. We numerically show that the characteristic modes of the MWS are significantly changed particularly near the slow-light-modes when the intrinsic loss is introduced into the system. In particular we show that the stopped-light-modes disappear even in the presence of an arbitrarily small amount of loss. Moreover, we find several novel properties such as a splitting of complex leaky modes in a lossy MWS.