Research progress of ultra-short laser pulse characterization

As an essential tool for generating attosecond lasers and exploring the microcosmic world of materials, the precise measurement of the temporal profile of ultra-short laser pulses is significant. Several methods for the generation of few-cycle laser pulses and widely employed characterization techniques were reviewed. The characterization techniques were generally classified into two major categories: frequency domain and time domain measurement. In the frequency domain, the envelope and phase of ultra-short pulses were reconstructed through the measurement of the spectral information generated by nonlinear processes. In the time domain, the temporal profile of the pulse was obtained by directly sampling the optical field information using the ultrafast gate. These two types of techniques have distinct emphases in different application scenarios. The frequency domain measurement is widely employed in fast characterization experiments due to its simplicity and convenience, while the time domain sampling is commonly used in ultrafast physics experiments that are directly associated with the optical field, as it allows for the direct acquisition of photoelectric field information.