2026-10-27
Time-Domain ADE-TLM Modeling of Graphene Interband Conductivity Using Vector-Fitted Complex-Conjugate Pole-Residue Pairs
By
Progress In Electromagnetics Research M, Vol. 140, 117-127, 2026
Abstract
In this paper, we model the interband conductivity of a graphene sheet using a rational-function expansion based on complex-conjugate pole-residue (CCPR) pairs via an efficient vector-fitting approach. We then incorporate the developed model into a time-domain transmission-line matrix (TLM) method with a voltage source and normalized admittance, representing graphene as an equivalent surface current density via an auxiliary differential equation (ADE) scheme. Reflection and transmission coefficients for electromagnetic (EM) wave interaction with an infinite graphene sheet are computed. Numerical results show excellent agreement with available theoretical data, demonstrating that interband conductivity contributions significantly modify graphene's electromagnetic response in the mid- and near-infrared regimes and cannot be neglected. Furthermore, the tunability of the transmission coefficient under varying temperatures and chemical potentials is investigated. The proposed method provides an alternative TLM-based approach for modeling graphene's full Kubo conductivity, extending the application domain of the TLM method from the far-infrared regime to the mid- and near-infrared regimes, and offers a new approach for the design and analysis of tunable graphene-based electromagnetic devices.
Citation
Mohamed Moumou, Khalid Mounirh, Soufiane El Adraoui, Mohammed Kanjaa, and Mohsine Khalladi, "Time-Domain ADE-TLM Modeling of Graphene Interband Conductivity Using Vector-Fitted Complex-Conjugate Pole-Residue Pairs," Progress In Electromagnetics Research M, Vol. 140, 117-127, 2026.
DOI:10.2528/PIERM26061505
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