2-D Extension of Spectrum-Splitting Fast-Fourier-Based Mode Solvers

Recently, a one-dimensional fast-Fourier-transform-based mode solver (FFT-MS) incorporating spectrum-splitting (SS) techniques has been proposed. This method calculates discontinuous fields from its Fourier decomposition without being affected by Gibbs phenomenon. In this letter, we present an extension of this approach in order to solve two-dimensional (2-D) problems. The validation of the resultant 2-D full-vectorial SS-FFT-MS is carried out by means of the study of a silicon-on-insulator photonic wire waveguide. The results achieved in this test show a clear improvement with respect to those obtained with the preceding FFT-MS.