Analysis of optical properties of fundamental-mode in waveguide tapered fibers

An analysis of optical properties of fundamental-mode in waveguide tapered fibers is theoretically investigated and realized in this paper. The waveguide device is tapering an SMF-28 fiber to few tens of micrometers of diameter. For discussing the cladding size of waveguide structure affects the fundamental-mode cutoff (FMC) and the optical characteristics of the devices, to etch outer cladding to reduce the pure-silica cladding diameter proceeded and to compare optical properties of FMC with non-etched cladding tapered fibers. Numerical results show the cutoff wavelength of FMC is mainly dominated by the size of squeezed core and slope of FMC could be influenced by the size of pure-silica cladding.