Unidirectional Emission of Active Eccentric Microring Cavities

Calculations of spectra, thresholds, and emission directivities of laser modes for active eccentric microring cavities are based on the lasing eigenvalue problem, which was reduced to the system of Muller boundary integral equations, and was discretized by the Galerkin method with trigonometric basis. In computational experiments, we demonstrate unidirectional emission of lasing, which is achievable with some assumptions on the position of the air hole in the cavity and its radius. In this work we obtain high directivity for unidirectional emission with the one pronounced ray in the directional pattern.