Tunable Autler-Townes-Like Resonance Splitting in a Bent Fiber-Optic Fabry-Perot Resonator: 3D Modeling and Experimental Verification

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.