We investigate the up-conversion process of broadband light from parametric down-conversion (PDC), focusing on the spatio-temporal spectral properties of the sum-frequency generated (SFG) radiation. We demonstrate that the incoherent component of the SFG spectrum is characterized by a skewed cigar-shaped geometry in space-time due to the compensation of spatial walk-off and group-velocity mismatch between the fundamental and the generated SFG fields. The results are illustrated both by a theoretical modeling of the optical system and by experimental measurements.
@article{arxiv.1308.2366,
title = {Space-time coupling in the up-conversion of broadband down-converted light},
author = {E. Brambilla and O. Jedrkiewicz and P. Di Trapani and A. Gatti},
journal= {arXiv preprint arXiv:1308.2366},
year = {2013}
}