Static-to-dynamic field conversion with time-varying media

Abstract

In this Letter, we theoretically demonstrate that a uniform static electric field distribution can be partially converted to radiation fields when a portion of the medium undergoes a temporal change of its permittivity. An in-depth theoretical investigation of this phenomenon is developed for a dielectric block with a step-like temporal change located inside a waveguide charged with a DC voltage source. Closed analytical expressions are derived for the radiated electric and magnetic fields. The exchange of energy between the electrostatic and electromagnetic fields is discussed. The reconciliation between the seemingly contradictory temporal and spatial boundary conditions for the electric and magnetic fields at the interface of the time-varying dielectric block is analyzed and elucidated. Our findings may provide an alternative solution for generating electromagnetic radiation based on time-varying media.

36 pages (16 pages of main text and 20 pages of supplementary materials), 8 figures (4 figures in the main text and 4 figures in the supplementary materials)

References in corpus (1)

• Time-Varying Materials in Presence of Dispersion: Plane-Wave Propagation in a Lorentzian Medium with Temporal Discontinuity

Cited by in corpus (6)

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• Stationary Charge Radiation in Anisotropic Photonic Time Crystals
• Plasmonic Time Crystals
• Electron Scattering at a Potential Temporal Step Discontinuity
• Generation and Enhancement of Persistent Nanoscale Magnetization in All-Dielectric Metasurfaces by Optically Injected and Localized Free Carriers