Triple-optical autocorrelation for direct optical pulse-shape measurement

Abstract

Triple optical autocorrelation of femtosecond optical pulses was realized simply with third-harmonic-generation technique. This optical technique provides complete knowledge of transient pulse intensity variation directly in time domain. Only analytic calculation is needed to obtain the pulse-shape from data without direction-of-time ambiguity. Combined with a spectral measurement and the Gerchberg-Saxton algorithm, except for pulses with complete temporal and spectral symmetry that will cause a twofold ambiguity, exact phase variation in time can also be retrieved through an iterative calculation with an O(n) complexity.

Characterizing the Statistics of a Bunch of Optical Pulses Using a Nonlinear Optical Loop Mirror

“…Although this technique is able to estimate the duration of pulses down to the few fs range, it provides little additional information. The autocorrelation however has been adapted and extended and several techniques were developed that allow complete pulse profile characterization (amplitude and phase of the electric field) [2][3][4][5][6]. One noticeable example is the FROG (Frequency Resolved Optical Gating) technique [2], which combines optical autocorrelation with spectral analysis.…”

Characterization of ultrashort optical pulses: a comparison between toad and frog

“…The iterative algorithm, which TOAD used, is Gerchberg-Saxton (GS) algorithm. With a measured spectrum and the pulse-shape calculated from triple-correlation [I], GS algorithm can retrieved the phase information of pulses [2]. To inspect the accuracy of the GS algorithm developed for TOAD, we compare it with the polarization gating FROG using computer simulation.…”

“…In the later 1960, it was shown that a triple-correlation is sufficient to determine the temporal intensity of a laser pulse with a direct mathematical calculation [I]. Direct third-harmonic-generation (THG) implementation of this proposal was realized on mode-locked Cr:forsterite and Tixapphire laser with the method of Triple-Optical Autocorrelation for Direct pulse-shape measurement (TOAD) [2]. In this report, we compare TOAD with commonly used method, FROG, by performing both methods on the same optical pulses.…”