title: Comparison of continuous-wave terahertz wave generation and bias-field-dependent saturation in GaAs:O and LT-GaAs antennas.
abstract: Terahertz wave (THz) photoconductive (PC) antennas were fabricated on oxygen-implanted GaAs (GaAs:O) and low-temperature-grown GaAs (LT-GaAs). The measured cw THz power at 0.358 THz from the GaAs:O antenna is about twice that from the LT-GaAs antenna under the same testing conditions, with the former showing no saturation up to a bias of 40 kV/cm, while the latter is already beginning to saturate at 20 kV/cm. A modified theoretical model incorporating bias-field-dependent electron saturation velocity is employed to explain the results. It shows that GaAs:O exhibits a higher electron saturation velocity, which may be further exploited to generate even larger THz powers by reducing the ion dosage and optimizing the annealing process in GaAs:O.
authors.forename: Kejian
authors.initials: K
authors.lastname: Chen
authors.forename: Yu-tai
authors.initials: YT
authors.lastname: Li
authors.forename: Mong-huan
authors.initials: MH
authors.lastname: Yang
authors.forename: Wing Yiu
authors.initials: WY
authors.lastname: Cheung
authors.forename: Ci-Ling
authors.initials: CL
authors.lastname: Pan
authors.forename: Kam Tai
authors.initials: KT
authors.lastname: Chan