Optical and Quantum Electronics

, Volume 43, Issue 11–15, pp 175–189 | Cite as

A search-and-track algorithm for controlling the number of guided modes of planar optical waveguides with arbitrary refractive index profiles

  • Tarek A. Ramadan


A search-and-track algorithm is proposed for controlling the number of guided modes of planar optical waveguides with arbitrary refractive index profiles. The algorithm starts with an initial guess point in the parameter space that supports a specific number of guided modes. Then, it searches for, and tracks, the boundaries of this space or another space supporting different number of modes. It does so by monitoring the sign of a unified cutoff dispersion function. The algorithm is applied to both symmetric and asymmetric silicon-based parabolic-index waveguides. It shows that unlike asymmetric waveguides, the single-mode condition of symmetric waveguides is controlled by TM-, as opposed to TE-, polarization. This abnormal polarization control is strongest for high index contrast waveguides of sub-micrometer core sizes. The results are verified by full-vectorial beam propagation method.


Graded index Integrated optics Numerical analysis Optical waveguides Step index Waveguide theory 


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Copyright information

© Springer Science+Business Media, LLC. 2011

Authors and Affiliations

  1. 1.Department of Physics, Faculty of ScienceKuwait UniversitySafatKuwait
  2. 2.Electronics and Electrical Communication Engineering DepartmentAin Shams UniversityCairoEgypt

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