A new physical approach to the implementation of amplitude modulators for terahertz (THz) radiation is proposed based on a tunable frequency-selective metasurface with integrated GaN/AlN transistors. The fabricated prototypes exhibit an electrically controlled depth of modulation of up to 92% at 128 GHz and a switching speed of 1.3 µs. Numerical simulation of the THz response of modulators shows good agreement with the experimental data. The obtained results can be used for the development of ultrafast active devices for terahertz wireless communication and imaging systems.
Titenko et al. (Sun,) studied this question.