  A novel 3-D higher-order finite-difference time-domain framework with complex
frequency-shifted perfectly matched layer for the modeling of wave propagation
in cold plasma is presented. Second- and fourth-order spatial approximations
are used to discretize Maxwell's curl equations and a uniaxial perfectly
matched layer with the complex frequency-shifted equations is introduced to
terminate the computational domain. A numerical dispersion study of second- and
higher-order techniques is elaborated and their stability criteria are
extracted for each scheme. Comparisons with analytical solutions verify the
accuracy of the proposed methods and the low dispersion error of the
higher-order schemes.
