Semiempirical relation for curved optical waveguide design in the edge-guided mode regime

A semiempirical relation has been developed for determining the minimum allowable radius of curvature of a circular waveguide with an edge-guided fundamental mode. The specified parameters are the wavelength, the effective refractive index of the waveguide, the lateral index step, and the allowable radiation loss coefficient. This relation was fitted and verified against numerically evaluated solutions of Maxwell's equations in two dimensions for lateral index steps 0.01< Delta N<0.1, for effective indices of refraction 3>