A mathematical framework for tunable metasurfaces. Part II

Article type: Research Article

Authors: Ammari, Habib^{; *} | Imeri, Kthim | Wu, Wei

Affiliations: Department of Mathematics, ETH Zürich, Rämistrasse 101, CH-8092 Zürich, Switzerland. E-mails: habib.ammari@math.ethz.ch, kimeri@sam.math.ethz.ch, wei.wu@sam.math.ethz.ch

Correspondence: [*] Corresponding author. E-mail: habib.ammari@math.ethz.ch.

Abstract: This paper is concerned with wave propagation inside a cavity with a tunable boundary condition. It is a follow-up of [Asympt. Anal. (2019), to appear]. Cavities, because they trap waves for long times due to their reflecting walls, are used in a vast number of scientific domains. Indeed, in these closed media and due to interferences, the free space continuum of solutions becomes a discrete set of stationary eigenmodes. These enhanced stationary fields are commonly used in fundamental physics to increase wave-matter interactions. The eigenmodes and associated eigenfrequencies of a cavity are imposed by its geometrical properties through the boundary conditions. In this paper, we show the effect of a small change of boundary condition on the Green’s function of the cavity. This is achieved through the use of a tunable reflecting metasurface. The boundary condition can be switched from Dirichlet to Neumann at some specific resonant frequencies.

Keywords: Tunable metasurface, cavity, field enhancement

DOI: 10.3233/ASY-191521

Journal: Asymptotic Analysis, vol. 114, no. 3-4, pp. 181-209, 2019