title: Joint spectrum of photon pairs measured by coincidence Fourier spectroscopy.
abstract: We propose and demonstrate a method for measuring the joint spectrum of photon pairs via Fourier spectroscopy. The biphoton spectral intensity is computed from a two-dimensional interferogram of coincidence counts. The method has been implemented for a type-I downconversion source using a pair of common-path Mach-Zehnder interferometers based on Soleil compensators. The experimental results agree well with calculated frequency correlations that take into account the effects of coupling into single-mode fibers. The Fourier method is advantageous over scanning spectrometry when detectors exhibit high dark count rates leading to dominant additive noise.
authors.affiliation: Instiute of Physics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Toruń, Poland. wwasil@fuw.edu.pl
authors.forename: Wojciech
authors.initials: W
authors.lastname: Wasilewski
authors.forename: Piotr
authors.initials: P
authors.lastname: Wasylczyk
authors.forename: Piotr
authors.initials: P
authors.lastname: Kolenderski
authors.forename: Konrad
authors.initials: K
authors.lastname: Banaszek
authors.forename: Czesław
authors.initials: C
authors.lastname: Radzewicz