Algorithm for high-resolution single-shot THz measurement using in-line spectral interferometry with chirped pulses

Z. P. Jiang and X. C. Zhang demonstrated a single-shot THz diagnostic based on spectral encoding of a chirped optical probe pulse. This technique is thought to have an inherent uncertainty principle-imposed temporal resolution limitations. In this letter, we describe a method to recover the THz field without distortions, surpassing previous resolution limitations. Our approach is based on interpreting the spectral encoding experiment as in-line spectral interferometry, analogous to Gabor's in-line spatial holography. We recover the THz field from the interferogram and the characterized probe by using Tikhonov regularization combined with lower and upper triangular decomposition. (c) 2005 American Institute of Physics.