A Novel Fabry-Perot Microcavity Based on Nonperiodic High-Index-Contrast Subwavelength Gratings

We report a novel Fabry-Perot (F–P) microcavity based on axisymmetric nonperiodic high-index-contrast subwavelength gratings (HCGs), which is a parallel structure with the bottom mirror that consists of axisymmetric aperiodic HCGs and distributed bragg reflectors. The special design of the bottom mirror effectively confines the light to a smaller area. Compared with the conventional F-P microcavity, the effective mode volume of the proposed novel F-P microcavity is greatly reduced and the quality factor is increased by 4.2 times, reaching 8158.