Diffraction Phenomena in Time-Varying Metal-Based Metasurfaces Alex Amor, Antonio Moreno Rodríguez, Salvador Padilla De La Torre, Pablo Valenzuela Valdes, Juan Francisco This paper presents an analytical framework for the analysis of time-varying metal-based metamaterials. Specifically, we particularize the study to time-modulated metal-air interfaces embedded between two different semi-infinite media that are illuminated by monochromatic plane waves of frequency ω0. The formulation is based on a Floquet-Bloch modal expansion, which takes into account the time periodicity of the structure (Ts = 2π/ωs) and integral-equation techniques. It allows us to extract the reflection and transmission coefficients as well as to derive nontrivial features about the dynamic response and dispersion curves of time-modulated metal-based screens. In addition, the proposed formulation has an associated analytical equivalent circuit that gives a physical insight into the diffraction phenomenon. Similarities and differences between space- and time-modulated metamaterials are discussed via the proposed circuit model. Finally, some analytical results are presented to validate the present framework. Good agreement is observed with numerical computations provided by a self-implemented finite-difference time-domain (FDTD) method. Interestingly, the present results suggest that time-modulated metal-based screens can be used as pulsed sources (when ωs ω0), beam formers (ωs ∼ ω0) to redirect energy in specific regions of space, and analog samplers (ωs ω0). 2023-06-26T11:39:55Z 2023-06-26T11:39:55Z 2023-04-05 journal article antonio Alex Amor et al. Diffraction Phenomena in Time-Varying Metal-Based Metasurfaces. Phys. Rev. Applied 19, 044014 (2023)[DOI: 10.1103/PhysRevApplied.19.044014] https://hdl.handle.net/10481/82826 10.1103/PhysRevApplied.19.044014 eng http://creativecommons.org/licenses/by-nc-nd/4.0/ open access Attribution-NonCommercial-NoDerivatives 4.0 Internacional American Physical Society