An LT-GaAs Terahertz Photoconductive Antenna With High Emission Power, Low Noise, and Good Stability

Semiconductor material is important to the performance of the terahertz (THz) photoconductive antenna. In this paper, we investigate the relationship between THz wave emission efficiency, noise, and stability to the material properties of fabricated low-temperature (LT) GaAs and semi-insulating GaAs antennas with the same structure, and compare their emission power, signal-to-noise ratio, and stability under the same experimental conditions. Both theoretical analysis and experimental results reveal that the LT-GaAs antenna has high THz wave emission efficiency, low noise, and high stability due to its short carrier lifetime and high resistivity, which provides us with guidance for the fabrication of high-performance photoconductive antennas.