Augmented low index waveguide for confining light in low index media
Guiding light in the low index region of a high refractive index contrast waveguide can be beneficial for many applications including sensing, nonlinear optics and electro-optics. Existing methods to achieve this goal suffer from fabrication complexity, large loss, or poor optical confinement. We propose a simple structure to achieve a significant enhancement of light confinement in the low index medium. We explain the guiding principle of this structure using geometrical optics, and suggest a number of applications where this guiding structure can provide significant performance benefits. The combination of simplicity, ease of fabrication, and good confinement makes this waveguide an attractive choice for a wide range of applications. To illustrate this, we consider the integration of a nonlinear polymer with a silicon photonic waveguide, and show that significantly better performance with an easier fabrication process can be achieved using this new scheme.
© 2017 by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Issue online: 19 May 2017; Version of record online: 19 May 2017; Manuscript Accepted: 24 April 2017; Manuscript Revised: 17 March 2017; Manuscript Received: 7 September 2015.