Spatial coherence effects on second- and fourth-order temporal interference
Abstract
We report the results of two experiments performed with two-photon light, produced via collinear degenerate optical spontaneous parametric downconversion (SPDC), in which both second-order (one-photon) and fourth-order (two-photon) interferograms are recorded in a Mach-Zehnder interferometer (MZI). In the first experiment, high-visibility fringes are obtained for both the second- and fourth-order interferograms. In the second experiment, the MZI is modified by the removal of a mirror from one of its arms; this leaves the fourth-order interferogram unchanged, but extinguishes the second-order interferogram. A theoretical model that takes into consideration both the temporal and spatial degrees-of-freedom of the two-photon state successfully explains the results. While the temporal interference in the MZI is independent of the spatial coherence of the source, that of the modified MZI is not.
Cite
@article{arxiv.0805.0641,
title = {Spatial coherence effects on second- and fourth-order temporal interference},
author = {Timothy Yarnall and Ayman F. Abouraddy and Bahaa E. A. Saleh and Malvin C. Teich},
journal= {arXiv preprint arXiv:0805.0641},
year = {2009}
}