Efficient terahertz generation by ordered arrays of GaAs nanowires

THz generation under the excitation by ultrashort optical pulses from ordered arrays of GaAs nanowires is reported. It was found that the efficiency of THz radiation generation increases due to the resonant leaky mode excitation in nanowires. The THz generation mechanisms have been identified. It is shown that the efficiency of the terahertz generation at optimum geometrical parameters of an array of semiconductor nanowires is greater than the corresponding value for bulk semiconductor p-InAs, which is the most effective THz emitter.