We report a quasi-semicircle GaN ultraviolet microcavity laser. Poincaré map of the quasi-semicircle cavity shows periodic, quasi-periodic and chaotic optical trajectories. Finite-element-method optical near-field distribution patterns of the periodic optical modes agree with the optical loops in the quasi-semicircle cavity. Based on the numerical results, optically pumped lasing experiment shows that ultraviolet multimode lasing action from different optical resonance modes can be effectively stimulated at low pumping intensity in the quasi-semicircle GaN cavity, and the side-mode suppression phenomenon can be obtained at high pumping intensity. Because the possible period optical loops are quasi-periodic and unstable, the quasi-whispering-gallery mode lasing with higher quality factor prefer to dominate the lasing action under high pumping. The experimental and simulated lasing modes suggest that side-mode suppression phenomenon can be caused by the mode competition between quasi-whispering-gallery modes and other quasi-periodic modes.

中文翻译：

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紫外准半圆微激光腔中的边模抑制

我们报告了一种准半圆 GaN 紫外微腔激光器。准半圆腔的庞加莱图显示了周期性、准周期性和混沌的光学轨迹。周期性光学模式的有限元法光学近场分布模式与准半圆腔中的光学回路一致。基于数值结果的光泵激激射实验表明，准半圆GaN腔在低泵浦强度下可有效激发不同光学共振模式的紫外多模激射作用，在高泵浦时可得到边模抑制现象。强度。由于可能的周期光环是准周期性的且不稳定的，因此具有较高品质因数的准耳语-画廊模式激光更倾向于在高泵浦下主导激光作用。