Spatiotemporal Isotropic-to-Anisotropic Meta-Atoms

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Pacheco-Peña, Victor, Engheta, Nader
Format: Preprint
Published: 2021
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866908552931573760
author Pacheco-Peña, Victor
Engheta, Nader
author_facet Pacheco-Peña, Victor
Engheta, Nader
contents Metamaterials and metasurfaces are designed by periodically arranged subwavelength geometries, allowing a tailored manipulation of the electromagnetic response of matter. Here, we exploit temporal variations of permittivity inside subwavelength geometries to propose the concept of spatiotemporal meta-atoms having time-dependent properties. We exploit isotropic-to-anisotropic temporal boundaries within spatially subwavelength regions where their permittivity is rapidly changed in time. In so doing, it is shown how resulting scattered waves travel in directions that are different from the direction of the impinging wave, and depend on the values of the chosen anisotropic permittivity tensor. To provide a full physical insight of their performance, multiple scenarios are studied numerically such as the effect of using different values of permittivity tensor, different geometries of the spatiotemporal meta-atom and time duration of the induced isotropic-to-anisotropic temporal boundary. The intrinsic asymmetric response of the proposed spatiotemporal meta-atoms is also studied demonstrating, both theoretically and numerically, its potential for an at-will manipulation of scattered waves in real time. These results may open new paradigms for controlling wave-matter interactions and may pave the way for the next generation of metamaterials and metasurfaces by unleashing their potential using four-dimensional (4D) unit cells.
format Preprint
id arxiv_https___arxiv_org_abs_2106_12471
institution arXiv
publishDate 2021
record_format arxiv
spellingShingle Spatiotemporal Isotropic-to-Anisotropic Meta-Atoms
Pacheco-Peña, Victor
Engheta, Nader
Optics
Applied Physics
Metamaterials and metasurfaces are designed by periodically arranged subwavelength geometries, allowing a tailored manipulation of the electromagnetic response of matter. Here, we exploit temporal variations of permittivity inside subwavelength geometries to propose the concept of spatiotemporal meta-atoms having time-dependent properties. We exploit isotropic-to-anisotropic temporal boundaries within spatially subwavelength regions where their permittivity is rapidly changed in time. In so doing, it is shown how resulting scattered waves travel in directions that are different from the direction of the impinging wave, and depend on the values of the chosen anisotropic permittivity tensor. To provide a full physical insight of their performance, multiple scenarios are studied numerically such as the effect of using different values of permittivity tensor, different geometries of the spatiotemporal meta-atom and time duration of the induced isotropic-to-anisotropic temporal boundary. The intrinsic asymmetric response of the proposed spatiotemporal meta-atoms is also studied demonstrating, both theoretically and numerically, its potential for an at-will manipulation of scattered waves in real time. These results may open new paradigms for controlling wave-matter interactions and may pave the way for the next generation of metamaterials and metasurfaces by unleashing their potential using four-dimensional (4D) unit cells.
title Spatiotemporal Isotropic-to-Anisotropic Meta-Atoms
topic Optics
Applied Physics
url https://arxiv.org/abs/2106.12471