Distortion of the intense terahertz signal measured by spectral-encoding technique

Abstract

We demonstrate that a distortion of the terahertz signal measured by spectral-encoding technique occurs when the original signal is too intense. We found that the stronger the original signal is, the more severe the distortion of the retrieved signal will be. Our simulation reproduces this phenomenon and suggests that this distortion, which affects the application of the single-shot terahertz detection technique, comes from the neglect of the quadratic term of the modulation depth which reflects the strength of the terahertz signal in the retrieving process. A possible simple method is proposed to eliminate this distortion.