Fabrication of low OH loss holey fibers with varying air hole sizes and their optical properties

Abstract

We experimentally investigate a flexible fabrication technique for low OH and transmission losses holey fibers with a Ge-doped core and air holes in a silica cladding region. Versatile holey fibers of different size, pitch, and shape of air holes were achieved by controlling the temperature and heating time of the holey fiber preform. In addition, we suppress the OH loss of less than ∼0.323dB/km at 1383nm. After fabricating holey fibers, we measure their optical properties including cut-off wavelength, mode field diameter, splicing loss, dispersion, bending loss, and polarization dependent loss based on the size of air holes. The total transmission loss was measured to be ∼0.226dB/km at 1550nm by improving the fabrication process. After fabricating optical patch cord based on holey fibers, we measured the long-term stability of the fabricated holey fiber by using the temperature cycling technique for 24 and obtained low power fluctuation of 0.2dB. We achieve the high quality holey fiber with a low bending loss of ∼0.04dB/turn under a bending radius of 2.5mm at 1550nm. We also obtain a tunable band rejection filter with a number of bending turns.