An effective unconditionally stable algorithm for dispersive finite difference time domain simulations

Abstract

Unconditionally stable formulations of the stretched coordinates perfectly matched layer (SCPML) are presented for truncating linear dispersive finite difference time domain (FDTD) grids. In the proposed formulations; the Crank Nicolson and the Bilinear frequency approximation techniques are incorporated with the SCPML to obtain the update equations for the field components in linear dispersive media. Numerical example carried out in one dimensional Lorentz dispersive FDTD domain is included and it has been observed that the proposed formulations not only give accurate results but also remove completely the stability limit of the conventional FDTD algorithm.