2-DIMENSIONAL MEASUREMENT OF THE TEMPORAL CORRELATION-FUNCTION OF PICOSECOND LIGHT-PULSES RECORDED IN A PHOTOREFRACTIVE CRYSTAL

We describe a novel method for the measurement of spatially two-dimens ional temporal amplitude correlation function of two coherent short li ght pulses with picosecond resolution in which the light pulses are re corded in a volume-holographic medium and the recorded information is read out by direct measurement of the spatial distribution of the grat ing formed in the medium. The feasibility of this method was experimen tally proved by means of a photorefractive LiNbO3:Fe crystal and a 3.5 -ps frequency-doubled mode-locked Nd:YAG laser. We measured the diffra ction of a cw He-Ne laser by the grating formed in the crystal and cal culated its envelope function by inversely solving coupled-wave equati ons. (C) 1997 Optical Society of America.