Multiple Photoconductive Antennas Terahertz Power Synthesis Technology Based on Time-Domain Waveform Consistency

In order to increase the terahertz output power of the photoconductive antenna, a new multiple terahertz power synthesis technology based on terahertz time domain spectroscopy waveform consistency is proposed. The dipole photoconductive antenna with 500-μm aperture and a plurality of delay lines are used to build multiple terahertz power synthesis system. A synthesis efficiency evaluation method is proposed on the basis of the temporal coherence degree. The terahertz time-domain spectroscopy signals can be generated synchronously by virtue of the precise control of multiple delay lines, which can be realized the maximizing frequency domain peak power. Experimental results showed that the synthesized time-domain spectroscopy signal peaks and frequency domain power peaks are maximized, when the terahertz optical path difference is consistent. Two channel, three channel, and four channel synthetic temporal coherence values are 99.47%, 90.45%, and 83.37%, respectively, and the terahertz radiation power peaks can reach 1.94, 2.27, and 2.45 times the peaks before synthesis, respectively.