Parabolic temporal lensing and spectrotemporal imaging: a femtosecond optical oscilloscope

Similariton-Based Spectral Interferometry for Signal Analysis on Femtosecond Time Scale

“…Particularly, the pulse compression ratio is as high as the spectral broadening factor is [41], the resolution of the femtosecond oscilloscope, based on the similariton-induced parabolic lens is given by the bandwidth of similariton [22], and for the similariton-based SI, the application range is as large as broadband the similariton-reference is [43,46].…”

“…A spectral detection of the SFG-signal will give also information on the chirp of similariton, modifying the cross-correlation technique to the cross-correlation frequency-resolved optical gating (XFROG) [49,50]. Our additional modification is the use of a dispersively chirped reference pulse, which provides a spectrally compressed SFG-signal in a wider spectral range, and thus, more efficient measurement [22,44]. Experimentally, the low-power pulse is directed into the dispersive delay line with anomalous dispersion (Dline; conventional prism compressor consisting of a 3.5-m separated SF11 prism pair with a reverse mirror) and stretch it 22 times, resulting in the pulse autocorrelation duration of 3.1 ps.…”

“…the femtosecond oscilloscope, based on the similariton-induced parabolic lens, is given by the bandwidth of similariton [22], and the application range for similariton-based SI [43] is as large as broadband the similariton-reference is. The pulse compression ratio is also as high as the spectral broadening factor is [40,41].…”

“…Experimentally, our SI study permitted the complete characterization of the nonlinear-dispersive similariton of up to 5 THz bandwidths [36,37]. For broadband similaritons (of up to 50-THz bandwidths), we applied the chirp measurement technique through spectral compression and frequency tuning in the sumfrequency generation process [22,44,45].…”

“…Experimentally examining the similariton-based SI, we carried out the comparative measurements with a prototype of the femtosecond oscilloscope (FO) based on the pulse spectrotemporal imaging in the similariton-induced temporal lens. The resolution of such a similariton-based FO is given by the transfer function of the similariton's spectrum [22], and FO with a similariton-reference of the bandwidth of 50 THz bandwidths provides the direct measurement of temporal pulse in a spectrometer of 7 fs temporal resolution. In the comparative experiments, we demonstrate and study the methods of similariton-based SI and spectrotemporal imaging as two applications of similariton.…”