Fano-like lineshapes in whispering-gallery modes (WGMs) microresonators are of critical for many actual applications, such as high-sensitivity sensors, slow light, and optical switches. In this paper, we theoretically and experimentally demonstrate dynamic transmission lineshapes, including Lorentzian lineshapes, Fano-like lineshapes and gain-like lineshapes, with a simple system, where a surface nanoscale axial photonic (SNAP) microbottle is coupled to the transition of a tapered fiber by carefully choosing tapered fiber diameters. Controlled and robust coupling with a clean and almost equidistant spectrum for different axial modes is achieved while maintaining contact between the resonator and the taper. Our device offers five similar dynamic transmission lineshapes arranged in order simultaneously, demonstrating stable tuning and a high number of potential degrees of freedom in contrast to other coupling systems for single- or double-coupled microresonators. By using coupled-mode theory, these transmission lineshapes are fitted to explain these experiment observations. We also explore a tunable transmission spectra obtained by increasing the powers of the input laser. Our approach hold unique potential in sensitivity-enhanced sensing, quantum information processing, and all-optical switching.

中文翻译：

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鲁棒 SNAP 微瓶-锥形耦合系统中动态传输线形的实验观察

回音壁模式 (WGM) 微谐振器中的类 Fano 线形对于许多实际应用至关重要，例如高灵敏度传感器、慢光和光开关。在本文中，我们从理论上和实验上证明了动态传输线形，包括洛伦兹线形、类 Fano 线形和类增益线形，使用一个简单的系统，其中表面纳米级轴向光子 (SNAP) 微瓶耦合到锥形的过渡通过仔细选择锥形光纤直径来制造光纤。在保持谐振器和锥体之间的接触的同时，实现了对不同轴向模式具有干净且几乎等距的频谱的受控和稳健耦合。我们的设备提供了五个相似的动态传输线形状，同时按顺序排列，与用于单耦合或双耦合微谐振器的其他耦合系统相比，展示了稳定的调谐和大量的潜在自由度。通过使用耦合模式理论，拟合这些传输线形状来解释这些实验观察结果。我们还探索了通过增加输入激光功率获得的可调透射光谱。我们的方法在灵敏度增强传感、量子信息处理和全光开关方面具有独特的潜力。