Mesoscopic structures as quantum dots open a way for the efficient control and feeding of nano-antennas in the infrared and optical frequency ranges, in strong- and super-strong coupling regimes. What we see here is the possibility of realizing THz devices by exploiting new promising physical mechanisms enabling the excitation of mesoscopic structures via shot noise, Rabi and Rabi-Bloch oscillations, and direct interband THz transitions induced by optical excitation.