title: Ghost imaging schemes: fast and broadband.
abstract: In ghost imaging schemes information about an object is extracted by measuring the correlation between a beam that passed the object and a reference beam. We present a spatial averaging technique that substantially improves the imaging bandwidth of such schemes, which implies that information about high-frequency Fourier components can be observed in the reconstructed diffraction pattern. In the many-photon regime the averaging can be done in parallel and we show that this leads to a much faster convergence of the correlations. We also consider the reconstruction of the object image, and discuss the differences between a pixel-like detector and a bucket detector in the object arm. Finally, it is shown how to non-locally make spatial filtering of a reconstructed image. The results are presented using entangled beams created by parametric down-conversion, but they are general and can be extended also to the important case of using classically correlated thermal-like beams.
authors.forename: M
authors.initials: M
authors.lastname: Bache
authors.forename: E
authors.initials: E
authors.lastname: Brambilla
authors.forename: A
authors.initials: A
authors.lastname: Gatti
authors.forename: L
authors.initials: L
authors.lastname: Lugiato