Reduction of Wavelength Dependence of Coupling Characteristics Using Si Optical Waveguide Curved Directional Coupler
- 2 May 2014
- journal article
- Published by Institute of Electrical and Electronics Engineers (IEEE) in Journal of Lightwave Technology
- Vol. 32 (12), 2188-2192
- https://doi.org/10.1109/jlt.2014.2321660
Abstract
Directional couplers are widely used as one of the key components of optical integrated circuits. However, the coupling efficiency of the conventional directional coupler is highly sensitive to wavelength. This sensitivity degrades the characteristics of devices that contain directional couplers for wavelength division multiplexing transmission. A curved directional coupler has been proposed using silica optical waveguide as one of the coupler which realize wavelength insensitive, small footprint and tolerant to fabrication. In this paper, we theoretically investigated this curved coupler using Si wire waveguide and got results that the curved coupler whose bending radius of 21 μm and coupling length of 7.40 μm can reduce the wavelength dependence and achieve about a sevenfold enhancement of operational bandwidth in the transmittance variation range of -3 ± 0.1 dB compared with conventional directional coupler.Funding Information
- Grant-in-Aid for Scientific Research (¿24760271, ¿90202837)
- A-STEP Feasibility Study Program (¿AS242Z02305J)
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