2025/01/22 by Ayan Nussupbekov, Nussupbekov, Ayan, Juan‐Feng Zhu +11
Computer Science · #FOS: Physical sciences #Neural Networks and Reservoir Computing #Optics (physics.optics)
paper · pdf · doi:10.48550/arxiv.2501.12899
openalex publication_date 2025/01/22 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
This work investigates the effects of time-varying media, where optical properties change over time, on electromagnetic wave propagation, focusing on plane waves and free-electron evanescent waves. We introduce a switching parameter, τ, to model ultrafast switching in the femtosecond to nanosecond range. For plane-wave incidence at angular frequency ω0, we derive a generalized expression for the backward-to-forward flux ratio as a function of ω0 and τ, aligning with recent experimental data and providing a unified interpretation framework. For free-electron incidence, we observe intensity saturation in temporal transition radiation at I_\textrmmax for τ≤ τ_\textrm0, with both I_\textrmmax and τ_\textrm0 depending on electron speed. These results highlight the importance of precise τ control in experiments to probe time-varying media effectively.