First On-Sky Fringes with an Up-Conversion Interferometer Tested on a Telescope Array

Abstract

The Astronomical Light Optical Hybrid Analysis project investigates the combined use of a telescope array interferometer and nonlinear optics to propose a new generation of instruments dedicated to high-resolution imaging for infrared astronomy. The nonlinear process of optical frequency conversion transfers the astronomical light to a shorter wavelength domain. Here, we report on the first fringes obtained on the sky with the prototype operated at 1.55 μm in the astronomical H band and implemented on the Center for High Angular Resolution Astronomy telescope array. This seminal result allows us to foresee a future extension to the challenging midinfrared spectral domain.

Optical Interferometry with Quantum Networks

“…The requirement of interferometric stabilization at optical wavelengths and the weakness of light sources in this domain have precluded the widespread adoption of optical telescope arrays [5]. Notably, the weaker light intensities make phase-sensitive heterodyne detection infeasible due to vacuum fluctuations [6]; therefore, high-resolution optical telescopes are operated by directly interfering the collected light [7]. Then, the size of the array (and consequently resolution) is ultimately limited by transmission losses between telescope sites.…”

Multichannel spectral mode of the ALOHA up-conversion interferometer

“…Convincing preliminary results have been obtained in laboratory with a blackbody source (Gomes et al 2014), and recently on the sky (Darré et al 2016) through a collaboration with the CHARA Array team (ten Brummelaar et al 2005). These studies have been performed in the H astronomical band to take advantage of the mature technology dedicated to optical telecommunications.…”

Control of the coherence behavior in a SFG interferometer through the multipump phases command

“…For more than a decade we investigate a new concept of fiber interferometer involving a non-linear stage in each arm: the SFG interferometer. The main purpose of this research activity consists of an alternative technique for high resolution imaging with telescope array in the near and mid-infrared spectral domains [9,10]. To broaden the converted infrared spectrum of the instrument, we have proposed the use of a multispectral pump.…”