Optical control of millimeter waves using slot line on semiconductor plasma substrate

Efficient optical control of millimeter waves in a slot line on Si and GaAs substrate is discussed both theoretically and experimentally. Experiments in the frequency range of 35 GHz to 50 GHz are carried out using high resistivity Si and GaAs wafers. The attenuation of millimeter waves of more than 25 dB could be controlled by optical means using LEDs with 870 nm wavelength and 100 mW of optical power. The experimental results agree considerably well with the theoretical estimation based on the spectral domain method. The experimental results on the response of millimeter wave with high power, pulsed optical illumination are also included