Wavelength-Selective Fused Taper Couplers Utilizing Field Distribution Difference between Core and Cladding Modes

摘要

It is shown that wavelength-selective fused taper couplers can be made by using the large difference in field distribution between core and cladding modes. Fibres with high index difference and thin outside diameter are necessary to fabricate the couplers. Fused taper couplers are made of thin fibres with cladding diameter of 66.0-μm and index difference of 0.84%. The splitting ratio is more than 20dB in the 1.53-μm region and less than -20dB in the 0.8 to 1.0-μm region. The loss is less than 0.2dB and 0.4dB in the 1.53-μm and the 0.8 to 1.0-μm regions, respectively.