3D dielectric cuboids: An alternative for high-resolution terajets at THz frequencies

A mechanism to produce terajets at terahertz frequencies (THz) is numerically and experimentally demonstrated by simply using 3D dielectric cuboids. After evaluating the focusing performance, it is demonstrated that a quasi-symmetric focus is produced just at the output of the 3D cuboid when the refractive index is n=1.41. Moreover, the terajet performance is evaluated experimentally, demonstrating a good agreement with simulation results. Also, by using spherical metallic particles with different diameters, the capability to enhance the backscattering is demonstrated with an enhancement of ~1.53dB and ~10dB for metal particles with diameters d
₁
=0.1λ
₀
and d
₂
=0.25λ
₀
, respectively.