Antenna-boosted mixing of terahertz and near-infrared radiation

Abstract

Using moderate terahertz intensities of approximately 20-kW/cm 2 near 0.6 THz, together with simple antennas, we have observed up to 12 sidebands on a near IR laser. The high-order sidebands were generated at room temperature in a membrane containing GaAs/AlGaAs quantum wells. The antennas were rectangular apertures ∼0.2-mm long in a gold film evaporated onto the membrane. Comparing the intensities required to generate comparable sideband spectra with and without antennas, we estimate the local terahertz field was enhanced by a factor of 5-±-1, in agreement with finite difference time domain calculations. © 2014 AIP Publishing LLC.