Evaluation of spatio-spectral characterization methods for few-cycle pulses

Precise knowledge of the structure of ultrashort light pulses simultaneously in space and time is fundamental for their successful applications. To this end, various techniques have been developed that determine the spatio-spectral properties and couplings. Here, we report on a simple, enhanced version of a spatio-spectral metrology approach termed simplified INSIGHT. Furthermore, we compare two commonly used spatio-spectral diagnostic methods 'HASO multispectral' and 'INSIGHT'. As a source, we utilize a non-collinear optical parametric amplifier that supports few-optical-cycle pulses with an artificially introduced spatio-spectral coupling. While both techniques successfully resolve the introduced aberration, each has distinct practical advantages and disadvantages, which we investigate and discuss. Finally, we propose a practical way to assess the correctness of spatio-temporal characterization results.