Ultrabroadband THz – TDS
In our TeraWatt Laboratory we’ve built an ultrabroadband THz time domain spectrometer, capable of performing measurements in frequency range from 0.3 to 20 THz. Depending on type of sample, measurements can be carried out in a transmission or reflection mode – Fig. 1. More over our spectrometer incorporates a third optical beam – pump beam, and is capable of performing time resolved THz measurements with 100 fs time resolution.
In our spectrometer THz waves are generated from two-color laser-induced gas plasma, and then detected using air-biased coherent detection. In this scheme bandwidth is limited only by the bandwidth of the laser.
Figure 3 shows example of data obtained our ultrabroadband THz system, with comparison to data obtain conventional THz TDS system based on photoconductive antennas.