The optical properties of $\mathrm{Eu}$-doped $\mathrm{Ga}\mathrm{N}$ microdisks (MDs) are demonstrated. The MDs are based on OMVPE-grown $\mathrm{Eu}$-doped $\mathrm{Ga}\mathrm{N}$ by our applying a 600-nm-thick ${\mathrm{Al}}_{0.82}{\mathrm{In}}_{0.18}\mathrm{N}$ sacrificial layer. The resonant modes of 1.57-µm-diameter MDs are coupled with indirectly excited ${\mathrm{Eu}}^{3+}$ ions and enhance their radiative rate. We show a clear correlation between the radiative rate and the Q factor of the MD, accompanied by enhanced $\mathrm{Eu}$-related emission. For a cavity mode with a Q factor of 3680, the radiative rate is increased approximately 4.5 times by the Purcell effect. Determination of the polarization of the modes is achieved by detection of emitted light in the plane of the MD, and the designation of modes is supported by numerical calculations. Temperature-dependent measurements of a MD with a diameter of 5.8 µm show a shift of the resonant modes of 10 pm/K, while $\mathrm{Eu}$-related emission is stable (less than 1 pm/K). The resonant mode of a MD with a diameter of 1.57 µm shows a smaller temperature dependence of 7 pm/K.

中文翻译：

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GaN光盘中Eu3 +离子的赛尔效应增强辐射速率

的光学性质 $\mathrm{欧盟}$掺杂 $嘎\mathrm{ñ}$演示了微型磁盘（MD）。MD基于OMVPE增长$\mathrm{欧盟}$掺杂 $嘎\mathrm{ñ}$ 通过我们应用600纳米的厚度 ${铝}_{0.82}{在}_{0.18}\mathrm{ñ}$牺牲层。1.57 µm直径MD的共振模式与间接激发耦合${\mathrm{欧盟}}^{3+}$离子并提高其辐射速率。我们显示出 MD的辐射速率和Q因子之间明显的相关性，同时伴随着增强$\mathrm{欧盟}$相关排放。对于Q 因子为3680的腔模式，通过赛尔效应使辐射速率提高了约4.5倍。通过检测在MD平面内的发射光来确定模式的偏振，并且通过数值计算来支持模式的指定。直径为5.8 µm的MD的随温度变化的测量结果 表明，共振模式发生了10 pm / K的偏移，而$\mathrm{欧盟}$-相关的发射是稳定的（小于1 pm / K）。直径为1.57 µm的MD的共振模式 显示出较小的温度依赖性7 pm / K。