Interdigitated photoconductive antenna-based two-color femtosecond laser filamentation THz time-domain spectral detection.

Two-color femtosecond (fs) laser filamentation in the gas medium is an effective way to generate broadband and high intensity terahertz (THz) pulse. The interdigitated photoconductive antenna (iPCA) has the advantages of both broadband detection and high signal-to-noise ratio (SNR), which is a very effective way to detect the THz pulse produced by two-color fs laser filamentation. The THz signal from two-color fs laser filamentation is comprehensively characterized by the iPCA, which achieves high SNR, high sensitivity, and polarization detection. This work provides a new idea for high power broadband THz coherent detection.