Use of various nonlinear crystals to measure the duration of single ultrashort pulses

An investigation is made of the feasibility of using various uniaxial and biaxial nonlinear crystals to measure the autocorrelation function of a single picosecond optical pulse using the second-harmonic beam method. General requirements are formulated for the wave interaction geometry in a crystal in order to maximize the temporal resolution and sensitivity of the autocorrelator. An analysis is made of LiIO3, KDP, KB5O84H2O and LiCHOOH2O crystals. The optimum interaction geometry is determined and the scanning duration and upper measurement limit are calculated for each crystal. Measurements of these quantities are reported for an LiIO3 crystal autocorrelator.