Modeling Lorentz dispersive media in FDTD using the exponential time differencing method

In this paper, we present the formulation of update equations for modeling electromagnetic wave propagation in second-order pole Lorentz media using the ETD method. As will be shown later, the formulation will result in less memory storage requirement compared to the ADE method. Numerical results also indicate that the ETD method is more accurate compared with other methods such as the ADE method and PLRC method.