volume | PIER Journals

Abstract

Planar waveguides with an isotropic chiral core, called chirowaveguides, support the propagation of elliptically polarized modes, making them natural candidates for chiral sensing. We investigate the potential of chirowaveguides as optical sensors responding to changes in the circular birefringence of a medium covering the waveguide. Using first order approximations, we derive expressions for the sensitivities to refractive index and to changes in circular birefringence. The chiral sensitivity is proportional to the achiral sensitivity and to the eccentricity of the mode under consideration. Possible combinations of materials and design conditions for chirowaveguide sensors are discussed with reference to these results. The motivation for this study, besides its theoretical and academic importance, comes from potential applications for enantiomeric integrated optical devices.

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Prof. Stephan Guy

Dr. A. Bensalah-Ledoux

Dr. A. Stoita