Weak guidance analysis of the modal characteristics and waveguide dispersion of a new lightguide with a lemniscate of Bernoulli-type core cross section

Abstract

The purpose of this paper is to introduce a simple analytical technique based on scalar-wave approximation to study the modal characteristics of a new lightguide having a lemniscate of Bernoulli-type core cross section. This type of structure may be conceived as a practical situation wherein two cores are embedded in a common cladding. Using lemniscate cylindrical coordinates (ξ, η, z) and the weak guidance boundary conditions, the eigenvalue equation is derived. From this equation, the characteristic curves have been obtained and plotted for some low-order modes (ν = 0). Furthermore, denoting the normalized frequency parameter as ν and the normalized propagation constant as b', the variation (d(Vb') / dV) is also obtained and analyzed. © 2002 John Wiley & Sons, Inc. Microwave Opt. Technol. Lett.