A second-order correlation coefficient is defined to estimate the severity of second-order spatiotemporal couplings. The correlation coefficient is scale invariant, normalized, dimensionless, etc. Using this correlation coefficient, the spatial chirp of ultrashort pulsed Gaussian beams is studied. It can be shown that the spatial chirp of ultrashort pulsed Gaussian beams depends on the pulse width, spectrum shape, and local frequency shift characteristics, and different types of ultrashort pulsed Gaussian beams exhibit different second-order spatiotemporal couplings characteristics.
© 2009 Optical Society of America
Original Manuscript: June 5, 2009
Revised Manuscript: July 30, 2009
Manuscript Accepted: July 31, 2009
Published: September 9, 2009
Shuguang Zeng, Youquan Dan, and Bin Zhang, "Describing second-order spatiotemporal couplings in ultrashort pulses using correlation coefficient," J. Opt. Soc. Am. B 26, 1869-1874 (2009)