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arXiv · 2605.23374

Generalized Conductivity Modeling and Selective Harmonic Amplification in Time-Modulated Graphene Cavities

Ioannis M. Koutzoglou·Stamatios Amanatiadis·Nikolaos V. Kantartzis·Theodosios D. Karamanos
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Abstract

The selective harmonic enhancement in cavities formed by stacks of time-modulated graphene sheets and a reflecting boundary is investigated. A semi-analytic framework based on an operator formulation and the transfer matrix method is developed and validated against a modified finite-difference time-domain algorithm. The temporal dispersion of graphene is treated through both a generalized Taylor-expanded conductivity model and a reduced high-bias approximation. By employing particle swarm optimization to tune the cavity gaps, selected Floquet harmonics are engineered under distinct modulation regimes. Numerical results show strong enhancement of first-order sidebands in the high-bias regime, controlled third-order harmonic generation beyond the linear regime with an explicit trade-off between target amplification and total non-target leakage, and symmetry-induced purely even harmonic generation under zero-centered modulation.

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Ioannis M. Koutzoglou, Stamatios Amanatiadis, Nikolaos V. Kantartzis, Theodosios D. Karamanos. 2026-05-22. Generalized Conductivity Modeling and Selective Harmonic Amplification in Time-Modulated Graphene Cavities. https://arxiv.org/abs/2605.23374

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