All solid state single-shot Dispersion scan (D-Scan) for ultrashort laser pulses

Abstract: Ultrashort laser pulses play an important role in many applications in science and technology, from attosecond science to time resolved spectroscopy and material processing. For applications of ultrashort laser pulses, it requires a complete characterization of the electric field of the pulse, which includes both phase and amplitude of the electric field. The characterization of ultrashort laser pulses is very challenging, since we do not have a detector fast enough to measure electric field variations on short time scales such as femtoseconds. A novel characterization technique for ultrashort laser pulses, the dispersion scan (d-scan), was recently developed in Lund. Here, a new compact single-shot version of the d-scan called Single-Shot d-scan (Si-scan) was developed, to extend the characterization technique to broader spectral range and longer durations. This technique employs a Transverse Second Harmonic Generation (TSHG) crystal which introduces dispersion as well as generating the second harmonic, resulting in a D-scan trace, i.e. SHG spectrum as a function of dispersion. The spectral phase can be retrieved from the D-scan trace by using a phase retrieval algorithm. Within the course of this work, the dispersion properties of the TSHG crystal were measured by using white-light spectral interferometry. A compact imaging spectrometer to measure the Si-scan trace by using the cross Czerny-Turner imaging spectrometer technique, which has very low astigmatism, was build. D-scans recorded with the new system are presented.