All-Glass Leakage-Channel Microstructured Optical Fibers with Reduced Core Refractive Index

The results of a theoretical study of all-glass microstructured optical fibers (MOFs) with leakage channels, containing two layers of round fluorine-doped silica elements in the cladding and doped cores 20 µm in diameter with different reduced refractive indices, are presented. Numerical analysis of the properties of these MOFs was performed using the finite-element method (FEM). The leakage losses of fundamental and higher modes in the spectral range from 0.79 µm to 1.35 µm for bent MOF at a bending radius of 8 cm are calculated. It is shown that the considered MOF design provides efficient single-mode operation in the spectral range from 0.99 to 1.28 µm. The leakage losses at a wavelength of 1.05 µm are of no more than 0.056 dB/m for fundamental modes and no less than 12.3 dB/m for higher modes.