Reconfigurable Terahertz Array Antenna

Terahertz imaging with high speed acquisition and spatial resolution is desired in many practical applications. In this work, a proof of concept for high speed near-field imaging with sub-wavelength resolution using spatial light modulator is presented. An 8 channel THz detector array antenna with an electrode gap of 100 mu m and length of 5 mm is fabricated using the commercially available GaAs semiconductor substrate. Each array antenna can be excited simultaneously by spatially reconfiguring the optical probe beam. The detected spatial THz electric field can be recorded using 8 channel lock-in amplifiers. By scanning the probe beam along the length of the array antenna, a 2D image can be obtained with amplitude, phase and frequency information. The time taken to reconstruct the image is limited only by the speed of the delay line to record the THz pulse at each spatial location.