Broadband Two-Dimensional Far-Field Beam Profiling of Commercial CW Terahertz Photomixers from 0.2 to 1.5 THz

We present a systematic far-field characterization of four commercial PIN diode terahertz photomixers over the 0.2-1.5 THz frequency range using a two-dimensional (2D) raster scanning method. The emission pattern of each transmitter, equipped with an integrated hyper-hemispherical silicon lens, was characterized using a broadband Schottky diode receiver over a 35 mm x 35 mm grid grid. The results reveal consistent frequency-dependent beam divergence and the emergence of distinct Airy diffraction...