Photonic crystal heteroslab-edge microcavity with high quality factor surface mode for index sensing

In this report, we propose a photonic crystal heteroslab-edge microcavity design for optical index sensing, where the high quality (Q) surface mode is confined by mode-gap effect. By optimizing the barrier region of the microcavity, high Q factor of 6.6× 105 is obtained in simulations. Lasing actions with high Q factor and low threshold of 6400 and 0.55 mW are obtained from the real devices. High index sensing response and small detectable index variation of 625 nm per refractive index unit and 3.6× 10-6 are obtained in simulations.