Symplectic finite‐difference time‐domain scheme based on decomposition technique of the exponential operator for plasma media

Abstract

The electromagnetic waves propagation in dispersive media is modelled using symplectic finite-difference time-domain (SFDTD) method based on decomposition technique of the exponential operator. The numerical stability and the dispersion relationships are presented. The numerical dispersion and dissipation errors originated from SFDTD method for non-magnetised collisional plasma medium are computed by comparing the real part and imaginary of numerical wave number with this analytic wave number. The high accuracy and efficiency is also confirmed by computing the reflection and transmission coefficients for a non-magnetised collision plasma slab. The numerical results show that the SFDTD method not only improves computational efficiency but also needs less computer memory as compared with the existing FDTD method. It can also be seen clearly that the eigenfrequency of the cavity resonator is filled with plasma media offsets. This conclusion has potential applications in the design of new types of microwave devices.