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 s 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 δ 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 δ, 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.

中文翻译：

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六边形和椭圆形二维光学微腔中的边界圆角效应

本文采用有限元方法对两类非圆形GaN微腔系统的边界圆角效应进行了数值模拟。当舍入参数s六边形微腔的模量减小，正六边形的六个角逐渐变圆，结果表明光学模式逐渐从六边形回音壁模式（WGM）转变为完美的圆形WGM，模式的品质因数增加相应地。对于椭圆形微腔，结构参数δ当椭圆形微腔逐渐从体育场腔变为圆形腔时，从 0 增加到 1。仿真结果表明，品质因数随着δ，并且光学模式从高泄漏模式变为 WGM。我们的结果证明了边界圆角对六角形和椭圆形微腔中模式模式和品质因数的影响。