Photoconductive terahertz antennas based on GAN {LT-INXGA1-XN/GAN}

A material in the form of a multilayer structure based on LT-GaN grown on Al2O3 sapphire substrates with a crystallographic direction (0001) is proposed for the manufacture of terahertz photoconductive antennas. The structures contain active layers of InxGa1−xN/GaN. The mole fraction In in the InxGa1−xN quantum well region is chosen to be 0.42. At an optical pumping power of 57 MW and a bias voltage of 15 V, a photoconductive antenna on an optimized {LT-InxGa1−xN/GaN} structure emits terahertz pulses with an average power of 4.5 µW at a laser pulse repetition rate of 60 MHz. Time profiles and frequency spectra of Fourier amplitudes of terahertz pulses generated using LT-GaN-based antennas have been obtained.