We determine the stability condition and analyze the accuracy of the exponential and centered time-differencing schemes for finite-difference time-domain (FDTD) in an isotropic, homogeneous lossy dielectric with electric and magnetic conductivities σ and σ*, respectively. We show that these schemes are equivalent and determine that, for accuracy, both schemes must be used with a time step that finely resolves the electric and magnetic conduction current relaxation time scales. The implications of these results for perfectly matched layer (PML)type absorbing boundary conditions are discussed.
All Science Journal Classification (ASJC) codes
- Electrical and Electronic Engineering
- Fdtd methods