In this paper, an efficient Transmission Line Matrix (TLM) algorithm for modeling chiral media is presented. The formulation is based on auxiliary differential equations (ADE) of electric and magnetic current densities. Permittivity and permeability are assumed to follow the Lorentz model while chirality is assumed to follow the Condon model. The proposed method models the dispersive nature of permittivity, permeability, and chirality by adding both voltage and current sources in supplementary stubs to the conventional symmetrical condensed node (SCN) of the TLM method. The electromagnetic coupling appears explicitly in the update equations of the voltage and current sources. The algorithm is developed to simulate electromagnetic wave propagation in a chiral medium. The co-polarized and cross-polarized transmitted and reflected waves from a chiral slab due to a normal incident plane wave are calculated. Validation is performed by comparing the results obtained from the proposed method with those obtained analytically.

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In plasma physics, the interaction with electromagnetic waves is related to the electrons contained in plasma. To analyze this interaction, the behaviour of electrons contained must be understood and modeled. In this paper, a new TLM formulation for dispersive media called the exponential time differencing (ETD) transmission line matrix (TLM) technique is introduced to model the interaction with dispersive media. To verify the high accuracy and efficiency of this method, the reflection and transmission coefficients of electromagnetic wave through a non-magnetized collisional plasma slab are computed and compared to the analytical solution. The electron density in plasma can be distributed as a Epstein formula, and its distribution as a function of the grads coefficient σ, and the effect of this parameter and the electron collision frequency υ c on the reflection coefficient is calculated. The results show that with different values of σ and υ c , the reflection coefficient is affected and can be reduced.