Compact fiber microsphere coupling system and its temperature response characteristics

Abstract The compact and free-stand fiber-microsphere system was established to produce the whispering gallery modes (WGMs). In this system, the BaTiO 3 microsphere in the diameter of ∼73 μ m was placed and fixed in an air cone, which was prepared by cascade-splicing and tapering a single mode fiber with a hollow core fiber. Either the wavelength or the intensity of the reflected spectra changes as function of the environmental temperature. The corresponding sensitivities were determined to be 9.75 pm/°C and −0.0133 dBm/°C, respectively, during 30 °C–70 °C. The proposed composite fiber WGMs system is compact, stable, moveable, easily-integrated and flexibly-adjustable, which will pave its promising potential way to developing the novel biochemical probes with high performance.