DFG XFROG. A new method for characterizing weak blue ultrashort pulses

Summary form only given. Frequency-resolved optical gating algorithms have become a standard method for characterizing the amplitude and phase of the electric field of ultrashort pulses because of its flexibility and robustness. However, the standard FROG geometries like SHG FROG or THG FROG, which are based on the spectrally resolved correlation signal of two identical copies of the pulse, are not suited for all circumstances. However difference frequency generation cross correlation frequency resolved optical gating (DFG XFROG), which uses spectrally resolved difference frequency generation and a modified FROG algorithm, expands the FROG technique to the blue and UV spectral range.