Boundary rounding effect in the hexagonal and oval two-dimensional optical microcavity

Abstract

In this paper, the boundary rounding effects of two types of non-circular GaN microcavity system are numerically simulated by the finite element method. When the rounding parameter [Formula: see text] of the hexagonal microcavity decreases, the six corners of the regular hexagon are gradually rounded, the results show that the optical mode gradually changes from the hexagonal whispering-gallery mode (WGM) to the perfect circular WGM, and the quality factor of the modes increases correspondingly. For the oval microcavity, the structure parameter [Formula: see text] increases from 0 to 1 when the oval microcavity gradually changes from a stadium cavity to a circular cavity. The simulation results show that the quality factor increases with [Formula: see text], and the optical mode changes from high-leak mode to WGM. Our results demonstrate the effect of the boundary rounding on the mode pattern and quality factor in hexagonal and oval microcavities.