Fig. 4
Terahertz antenna and detection simulations. a Electromagnetic simulation model of an extended hemispherical silicon lens with a double-slot antenna as a feed. b Antenna gain at 1.3 THz as a function of the incident angle in the two principal planes, H-plane (dashed line) and E-plane (solid line). The H-plane (E-plane) is the plane containing the magnetic (electric)-field vector and the direction of maximum radiation49. c Effective detection area as a function of frequency. d Planck spectral irradiance at T = 3.0 K (solid line), and projected frequency-selective surface (FSS) filter transmission (dashed line) for blackbody measurements. e Computed photon rate power spectral density (PSD) corresponding to d. f Computed total detected photon rate (dashed line) and the corresponding detected power (solid line) as a function of the temperature of the blackbody emitter
