Noise Analysis and Optimization of Terahertz Photoconductive Emitters

The electromagnetic noise generated by terahertz photoconductive emitters was investigated, and the intensity of noise spectrum was analyzed by statistical method. The relationship between the noise of the emitter and the resistivity as well as carrier lifetime of the antenna material was obtained. And the effect of carrier lifetime and mobility of antennas on the THz generation efficiency was investigated. Based on those results, GaAs:O material was fabricated by an ion implantation technique to obtain the required performance. The signal-to-noise ratio of the GaAs:O emitter was remarkably improved compared with a SI-GaAs emitter at the same experimental condition.