Symmetry and Finite-Size Effects in Quasi-Optical Extraordinarily THz Transmitting Arrays of Tilted Slots

TL;DR

This paper investigates how symmetry breaking in quasi-optical THz transmitting arrays of tilted slots affects their resonance behavior, combining numerical simulations and experimental measurements to understand the underlying physics.

Contribution

It introduces a comprehensive analysis of symmetry effects on transmission resonances in THz arrays, supported by combined theoretical and experimental approaches.

Findings

Symmetry breaking leads to diverse transmission resonances.

Resonance characteristics evolve with array size.

Time-dependent emission of frequency components is observed.

Abstract

Extraordinarily transmitting arrays are promising candidates for quasi-optical (QO) components due to their high frequency selectivity and beam scanning capabilities owing to the leaky-wave mechanism involved. We show here how by breaking certain unit cell and lattice symmetries, one can achieve a rich family of transmission resonances associated with the leaky-wave dispersion along the surface of the array. By combining 2-D and 1-D periodic method of moments (MoM) calculations with QO terahertz (THz) time-domain measurements, we provide physical insights, numerical, and experimental demonstration of the different mechanisms involved in the resonances associated with the extraordinary transmission peaks and how these evolve with the number of slots. Thanks to the THz instrument used, we are also able to explore the time-dependent emission of the different frequency components involved.