Abstract
An optimized solution to the discrete numerical model for simulating
arbitrary dispersion by the finite-difference time-domain (FDTD) method is
derived for both the single-pole and two-pole frequency responses of
dispersive media. Based on the method of Maclaurin series expansion, the
derivation is aimed to suppress the redundant truncation errors into minimum
levels by eliminating the first several series terms of difference between
the numerical and theoretical solutions to a modeled susceptibility. The
accuracy of numerical approximation to theoretical dielectric functions
based on our proposed approach is shown to be exactly equivalent to the
bilinear transformation model for the single-pole dispersion response of the
modeled dispersive material, but higher than those of other two previously
reported models for a two-pole dispersion response of a modeled dispersive
material. The explicit coefficients of the proposed model for several
classical types of dispersive materials are derived and their corresponding
dominant truncation errors are given as well. Both the analytical and
simulation results obtained from the FDTD modeling of an exemplified
material, silver, demonstrate that the new model outperforms the other
models when they are incorporated into the fourth-order accurate FDTD
algorithm with small numerical dispersion error rather than in the
second-order one with large numerical dispersion error.
© 2010 IEEE
PDF Article
More Like This
Cited By
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Login to access Optica Member Subscription