The birefringence properties of two types of side-hole fibers have been numerically studied, based on which a Sagnac fiber interferometer employing ethanol-filled side-hole fibers is proposed and experimentally demonstrated for high-sensitive temperature measurement. Thanks to highly temperature-sensitive refractive index of ethanol infiltrated in the air holes of side-hole fibers, high-sensitive temperature measurement could be realized by monitoring fiber-birefringence-induced resonance wavelength shift of the fiber Sagnac interferometer in response to environmental temperature variation. Experimental results show that within a temperature range of 26 C to 54 C, there exists some critical temperature point around 40 C, on both sides of which the resonance dips exhibit inverse temperature-dependent shift behaviors. A temperature sensitivity of 1.10 nm/ C is experimentally achieved for our proposed side-hole fiber Sagnac interferometer.
In this paper, we propose a single-mode laser operating in the mid-infrared regime by exploiting parity-time (PT) breaking in a whispering gallery mode (WGM) micro-resonator based on air-clad hollow-core ZBLAN fibers. By introducing alternate gain–loss modulation regions with refractive indices respectively having the same real parts but opposite imaginary parts into the air hole clad region of the hollow-core fiber infiltrated with optical functional materials, a PT symmetry system could be set up and specific WGM in PT-broken state whose electric field distribution matches the gain–loss modulation pattern can be excited to realize single-mode laser emission around 5 μm. And moreover, simulation results indicate that high precision laser wavelength tuning with a sensitivity of 1.623 nm RIU−1 can be achieved by adjusting the refractive index of the functional materials filled into the cladding air holes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.