Terajets produced by 3D dielectric cuboids

TL;DR

This study demonstrates the numerical and experimental generation of terajets using 3D dielectric cuboids at terahertz frequencies, achieving subwavelength focusing and enhanced backscattering for potential applications in THz imaging.

Contribution

It introduces the concept of terajets produced by 3D dielectric cuboids at THz frequencies and validates their focusing and scattering properties experimentally.

Findings

Achieved subwavelength focusing with ~0.46λ0 resolution.

Demonstrated backscattering enhancement with metal particles.

Validated terajet generation experimentally at sub-THz frequencies.

Abstract

The capability of generating terajets using 3D dielectric cuboids working at terahertz (THz) frequencies (as analogues of nanojets in the infrared band) are introduced and studied numerically. The focusing performance of the terajets are evaluated in terms of the transversal full width at half maximum along x- and y- directions using different refractive indexes for a 3D dielectric cuboid with a fixed geometry, obtaining a quasi-symmetric terajet with a subwavelength resolution of ~0.46{\lambda}0 when the refractive index is n = 1.41. Moreover, the backscattering enhancement produced when metal particles are introduced in the terajet region is demonstrated for a 3D dielectric cuboid and compared with its 2D counterpart. The results of the jet generated for the 3D case are experimentally validated at sub-THz waves, demonstrating the ability to produce terajets using 3D cuboids.