Characterization of Supercontinuum and Ultraviolet Pulses by Using XFROG

Abstract

We present cross-correlation frequency-resolved optical gating (XFROG) measurements of supercontinuum pulses generated by using a photonic crystal fiber (PCF), and ultraviolet (UV) pulses generated by frequency doubling of infrared ultra-short pulses. Since supercontinuum pulses have broad spectra, XFROG measurement typically requires using an extremely thin nonlinear crystal which has a thickness of sub-ten microns. Instead of using such a thin crystal, we employed a relatively thick crystal which was mounted on a galvanometer in order to achieve a phase-matching over the whole spectral bandwidth of the supercontinuum pulses by a crystal-dithering technique. Experimental results of the retrieved phase and intensity were in fair agreement with the independently measured data.

Intensity–phase characterization of white-light continuum generated in sapphire by 280 fs laser pulses at 1053 nm

“…We assembled a home-built XFROG diagnostic based on sum-frequency generation (SFG) [24,35] in the nonlinear crystal BBO between a weak test pulse and strong gate pulse to characterize the WLC pulses described in the previous sections. Because of the huge bandwidth involved, much larger than the phase-matching bandwidth of any SFG geometry, we employed a multi-shot XFROG measurement technique with crystal-dithering [23,24,29], to overcome the phase-matching angular limitation of the nonlinear crystal.…”

Pulse compression of white-light continuum generated at 1053 nm in bulk sapphire: an experimental study

“…The SF10 material presents a rather high third-order dispersion (TOD) suitable for the previously measured cubic phase the measured output residual TOD could not make vanish without simultaneously having a large residual group delay dispersion (GDD); the GDD/TOD ratio of the whitelight generation proved impossible to match completely with our prism pair. The calculated values of GDD and TOD, added by the prism pairs with a separation of 1 cm with Brewster cut incident angle, are ~−210 fs 2 and ~−590 fs 3 , respectively, at a central wavelength of 725 nm [26]. The FROG traces and their temporal and spectral profiles are shown in figure 5(a)-(d).…”

“…This can be carried out by employing an optical parametric amplifier (OPA), seeded by a white-light continuum idler pulse [1] which should be compressed by appropriate schemes. The white-light continuum in fiber and optical medium is described and characterized by using the different types of cross-correlation frequency-resolved optical gating techniques [2][3][4][5]. The white-light continuum in the optical bulk material has the potential to be used as a seed and amplify in the femtosecond noncollinear optical parametric amplifiers [6][7][8][9].…”

Simultaneous Characterization of Two Ultrashort Optical Pulses at Different Frequencies Using a WS2 Monolayer

“…In an autocorrelation FROG measurement, two copies of the same pulse are combined inside a nonlinear medium. Alternatively, in a cross-correlation FROG measurement, a known reference pulse is combined with an unknown pulse to generate nondegenerate signals such as sum-frequency generation (SFG) or four-wave mixing (FWM). − …”