Time Domain Finite Difference Method In The Analysis Of Optical Waveguide Applications

Finite-Difference Time-Domain (FDTD) algorithm is a numerical method used in electromagnetic simulation developed in the middle of I 960s. FDTD has made some successful applications in the electromagnetic simulation of microwave and antenna system. In 1994, Berenger put forward a novel absorbing medium-Perfect Matched Layer (PML) as absorbing boundary, which makes FDTD algorithm has broader applications. Our research introduce FDTD algorithm to the analyses of optical waveguide, and use FDTD algorithm to analyze the propagation characters of cylindrical optical fiber and photonic crystal fiber.This paper introduces the principle of FDTD algorithm. Aiming at the character different optical waveguide in cylindrical coordinate system, we simplifies the FDTD algorithm, and get I D-FDTD (one dimensional Finite-Difference Time-Domain) and 2D-FDTD (two dimensional Finite-Difference Time-Domain) algorithm, which will greatly reduce the computing time and storage space of computer.Furthermore, as for the problems come from the PML as the absorbing boundary condition in the analyses of optical waveguide. we present a suitable medium parameter for PML, which get excellent absorbing effect in the analyses of optical waveguide.Last, the paper presents the result for the propagation characteristics for optical fiber and photonic crystal fiber. The results of propagation character, field distribution, chromatic dispersion chart are present in this paper. These results, especially from the photonic crystal fiber, which have great agreement with the theoretical result and the experimental result, are useful for the better understanding of the characteristics of optical waveguides and the design of optical devices.