We present a numerical and experimental study of resonance splitting in the transmission and reflection spectra of the Fabry–Perot resonator made of a bent section of a conventional single-mode optical fiber with metallized end faces. We show the splitting to be similar in nature to the well-known Autler–Townes effect and to arise from the strong coupling between the core mode and cladding whispering gallery mode of the bent fiber. The effect of all major parameters of the bent resonator on the splitting of its resonances is demonstrated. Potential applications of the observed effects in the field of precision optical refractometry as well as further research directions are discussed.

中文翻译：

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弯曲光纤法布里-珀罗谐振器中的可调谐 Autler-Townes 式谐振分裂：3D 建模和实验验证

我们对法布里-珀罗谐振器的透射和反射光谱中的共振分裂进行了数值和实验研究，该谐振器由具有金属化端面的传统单模光纤的弯曲部分制成。我们展示了分裂在本质上与众所周知的奥特勒-汤斯效应相似，并且是由弯曲光纤的纤芯模式和包层回音壁模式之间的强耦合引起的。演示了弯曲谐振器的所有主要参数对其谐振分裂的影响。讨论了所观察到的效应在精密光学折光测量领域的潜在应用以及进一步的研究方向。