Single Measurement Technique Of Terahertztime Domain Spectroscopy

Through the continuous development of terahertz technology,terahertz time-domain spectroscopy(THz-TDS)has been widely used in various fields.The traditional electro-optical scanning THz-TDS technology needs to interact with the terahertz wave through multiple pulses to make the detection light scan point by point delay,and the time domain signal can be formed through long time data collection.Detection of irreversible processes.In order to overcome this shortcoming,this paper studies the single-shot measurement technique of terahertz pulses.Single terahertz measurement technology can quickly measure some ultra-fast.irreversible processes,and has broad application prospects in protein denaturation,nuclear explosion simulation analysis and other fields.Based on the oblique wavefront method,a single measurement system was designed:a femtosecond pulsed laser was divided into two beams,and one beam was used as pump light to generate a tilted wavefront through the blazed grating,and phase matching was achieved in the lithium niobate crystal based on The light rectification effect produces high-power terahertz waves;the other beam is used as the detection light,which is detected by the orthogonal balance detection method,and is also modulated by the terahertz wave electric field after being blazed grating,and imaged on the CCD to achieve a single measurement.The time window of the system is 22.17ps,and the spectrum range covers 0.11.6THz.