In this paper we describe an upconversion detector in the mid infrared (around 3.5 μm). We take advantage of the PPLN ridge waveguide technology to achieve single photon detection at room temperature on a single spatial mode.
View Article and Find Full Text PDFIn the frame of sum frequency generation of a broadband infrared source, we aim to enlarge the converted bandwidth by using a pump frequency comb while keeping a high conversion efficiency. The nonlinear effects are simultaneously induced in the same nonlinear medium. In this paper, we investigate the spectral filtering effect on the temporal coherence behavior with a Mach-Zehnder interferometer using two pump lines.
View Article and Find Full Text PDFThis paper reports on the experimental implementation of an interferometer featuring sum frequency generation (SFG) processes powered by a pump spectral doublet. The aim of this configuration is to allow the use of the SFG process over an enlarged spectral domain. By analyzing the converted signal, we experimentally demonstrate a frequency spectral compression effect from the infrared input signal to the visible one converted through the SFG process.
View Article and Find Full Text PDFThis paper demonstrates the use of a nonlinear upconversion process to observe an infrared source through a telescope array detecting the interferometric signal in the visible domain. We experimentally demonstrate the possibility to retrieve information on the phase of the object spectrum of an infrared source by using a three-arm upconversion interferometer. We focus our study on the acquisition of phase information of the complex visibility by means of the phase closure technique.
View Article and Find Full Text PDFWe present a three-telescope space-based interferometer prototype dedicated to high-resolution imaging. This project, named multiaperture fiber-linked interferometer (MAFL), was founded by the European Space Agency. The aim of the MAFL project is to propose, design, and implement for the first time to the best of our knowledge all the optical functions required for the global instrument on the same integrated optics (IO) component for controlling a three-arm interferometer and to obtain reliable science data.
View Article and Find Full Text PDFSome varieties of photonic crystal fiber (PCF) have huge potential for high-resolution imaging in astronomy. They allow us to operate in a single-mode regime over a wide bandwidth keeping a high transmission level. Thus they may be used to carry wide spectral light over hundreds of meters.
View Article and Find Full Text PDFPhotonic crystal fibers (PCFs) are microstructured waveguides that are used in metrology, nonlinear optics, and coherent tomography. PCF studies are focused mainly on the improvement of dispersion properties and wide spectral single-mode operating domains. Consequently, in the astronomical context this kind of fiber is a good candidate for use in the design of a fiber-linked version of a stellar interferometer for aperture synthesis.
View Article and Find Full Text PDFWe report our experimental investigations of the influence of differential telescope-pointing errors on data corruption in an optical stellar interferometer. This effect was investigated theoretically as a function of the telescope antenna diagram, which depends on the aperture diameter. Using a laboratory breadboard consisting of a three-telescope array, we carried out the experiments with various aperture diameters and complex objects.
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