An efficient method for a coupled microsphere and waveguide system is proposed and demonstrated nu-merically and experimentally.In order to study the coupling characteristics of the microsphere-waveguide system, a two-dimensional (2D) model is exploited by the coupled theory firstly.A numerical simulation system is designed with the finite difference time domain ( FDTD) method.The relative intensity spectra and transmission spectra in the wavelength range from 600 nm to 1000 nm are acquired by processing the sample data after fast fourier transfor-mation ( FFT) .In the experiment, the quartz-microsphere is fabricated by melting the tip of a single-mode optical fiber.The tapered fiber, fabricated by using the heat-and-pull technique, is chosen as a waveguide to excite whis-pering gallery modes ( WGMs) of the microsphere.The microsphere-taper coupling system is tested and the results indicate that a very high quality ( Q) factor up to 2.3 ×106 and a high coupling efficiency up to 92.5％can be a-chieved by optimizing the microsphere position and orientation relative to the tapered fiber.These coupling charac-teristics can be well explained with the theoretical results.Such properties show its great potential in practical mi-crocavity sensing and micro-lasers.%提出了一种耦合微球和波导系统的有效方法,并在数值和实验上进行了论证.为了研究微球腔和波导系统的耦合特性,首先通过耦合模理论研究了这个系统的2D模型.通过有限时域差分法设计了一个数值仿真系统.在快速傅里叶变换(FFT)处理样本数据后,得到了波长范围从600 nm到1000 nm的相对强度谱曲线和传输谱曲线.在实验中,采用熔融单模光纤顶端的方法制得了石英材料微球腔.采用热拉技术制得了锥形光纤,用来作为激发微球腔中回音壁模式的波导.测试了这个微球腔-锥形光纤耦合系统,通过优化微球腔与锥形光纤的相对位置得到其品质因数高达2.3×106,耦合效率高达92.5％.这些耦合特性可以很好地用理论结果解释.这些特性表明了其在实际微腔传感和微型激光器中极具潜力.
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