Dual coupler coupled cavities optical gyroscope with enhanced performance

Abstract

In recent years, the development of a reliable, low cost, miniaturized optical gyroscope has been a subject of research and development in the scientific and industrial communities. Since the sensitivity of the optical gyroscopes is reduced with the sensor footprint, multi-ring configurations, such as the coupled resonator optical waveguide (CROW) and the triple ring resonator configuration (TRR), were suggested to increase the sensitivity of the small foot print optical gyroscopes. In this work, a dual coupler coupled cavities configuration is suggested to be used in optical gyroscopes to enhance their performance. The configuration consists of two resonators directly coupled to each other. The passive cavity is a dual coupler ring resonator and is inserted in the main cavity such that the circulating light is fed back to the main cavity by the drop port of the coupled cavity. This leads to a smaller full width half maximum (FWHM) and hence better sensitivity. The passive resonator is studied to find analytical expressions for the output electric field and the effect of rotation on this field. The shot noise-limit sensitivity is calculated and compared to the conventional passive gyroscope in two cases: for a constant source power and for a constant detected power. The effect of propagation loss is also studied. An order of magnitude potential enhancement in the sensitivity is shown for silica-on-silicon technology.