Thin terahertz detectors and emitters based on low-temperature grown GaAs on sapphire

Summary form only given. Several applications require thin terhertz (THz) detectors or emitters. For example, in near-field imaging applications, the emitter needs to be located close to a sample under investigation. In spectroscopy, very thin antennas benefit from the absence of spurious reflections, lower capacitance and lower dark current. We report on photoconductive antennas based on 1-/spl mu/m-thick low-temperature grown GaAs (LT GaAs) transferred to a sapphire substrate. This device is optically excited from the side of the transparent substrate. The antenna was compared to a conventional LT GaAs antenna using the time domain spectroscopy technique.