Abstract-Efficient terahertz generation from lightly ion-beam-treated semi-insulating GaAs photoconductive antennas

Caiming Sun,  Aidong Zhang,

http://iopscience.iop.org/article/10.7567/APEX.10.102202

An ion beam technique is used to lightly treat semi-insulating GaAs terahertz (THz) photoconductive antennas (PCAs), and a novel structure with two layers, a carrier acceleration layer and a carrier trapping layer, is demonstrated to afford high-efficiency, high-power THz emitters. The key roles of vacancy defects produced by the ion beam in efficient THz generation are systematically described. The peak distribution of defects at approximately 2.5 µm provides an effective trapping layer for photocarriers during THz generation. Hydrogen ion implantation under reasonable conditions (300 keV, 1 × 1015 cm−2) for fabrication of efficient GaAs PCAs is found to be reproducible.