Calculating Scattering Spectra using Time-domain Modeling of Time-modulated Systems
Keywords:cavity resonators, finite-difference time-domain method, time-varying circuits
Obtaining agreement between theoretical predictions that assume single-frequency excitation and finite-difference time-domain (FDTD) simulations that employ broadband excitation in the presence of time-varying materials is challenging due to frequency mixing. A simple solution is proposed to reduce artifacts in FDTD-calculated spectra from the frequency mixing induced by harmonic refractive index modulation applicable to scenarios in which second order and higher harmonics are negligible. Advantages of the proposed method are its simplicity and applicability to arbitrary problems including resonant structures.
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