Integrated-optic components are being increasingly used in astrophysics, mainly where accuracy and precision are paramount. One such emerging technology is nulling interferometry that targets high contrast and high angular resolution. Two of the most critical limitations encountered by nullers are rapid phase fluctuations in the incoming light causing instability in the interference and chromaticity of the directional couplers that prevent a deep broadband interferometric null. We explore the use of a tricoupler designed by ultrafast laser inscription that solves both issues. Simulations of a tricoupler, incorporated into a nuller, result in an order of a magnitude improvement in null depth.

Download full-text PDF

Source
http://dx.doi.org/10.1364/AO.423541DOI Listing

Publication Analysis

Top Keywords

nulling interferometry
8
achromatic photonic
4
photonic tricouplers
4
tricouplers application
4
application nulling
4
interferometry integrated-optic
4
integrated-optic components
4
components increasingly
4
increasingly astrophysics
4
astrophysics accuracy
4

Similar Publications

Exoplanets can be detected very close to stars using single-mode cross-aperture nulling interferometry, a photonic technique that relies on the inability of an anti-symmetric stellar point-spread function to couple to the symmetric mode of a single-mode fiber. We prepared an asymmetric field distribution from a laboratory point source using a flat geometric-phase-based pupil-plane phase-knife mask comprised of a planar liquid crystal polymer layer with orthogonal optical axes on opposite sides of a linear pupil bisector. Our mask yielded an on-axis laboratory point-source rejection (i.

View Article and Find Full Text PDF

High angular resolution imaging is an increasingly important capability in contemporary astrophysics. Of particular relevance to emerging fields such as the characterization of exoplanetary systems, imaging at the required spatial scales and contrast levels results in forbidding challenges in the correction of atmospheric phase errors, which in turn drives demanding requirements for precise wavefront sensing. Asgard is the next-generation instrument suite at the European Southern Observatory's Very Large Telescope Interferometer (VLTI), targeting advances in sensitivity, spectral resolution, and nulling interferometry.

View Article and Find Full Text PDF

In the past 10 years, adaptive wavefront interferometry (AWI) has been employed for measuring freeform surface profiles. However, existing AWI techniques relying on stepwise and model-free stochastic optimizations have resulted in inefficient tests. To address these issues, deterministic adaptive wavefront interferometry (DAWI) is firstly introduced in this paper based on backpropagation (BP), which employs a loss function to simultaneously reconstruct and sparsify initial incomplete interferometric fringes until they are nulled.

View Article and Find Full Text PDF

X-ray mirrors with single-digit nanometer height errors are required to preserve the quality of ultra-intense photon beams produced at synchrotron or free electron laser sources. To fabricate suitable X-ray mirrors, accurate metrology data is needed for deterministic polishing machines. Fizeau phase-shifting interferometers are optimized to achieve accurate results under nulled conditions.

View Article and Find Full Text PDF

This paper presents a non-nulling absolute interferometric method for fast and full-area measurement of aspheric surfaces without the necessity of any mechanical movement. Several single frequency laser diodes with some degree of laser tunability are used to achieve an absolute interferometric measurement. The virtual interconnection of three different wavelengths makes it possible to accurately measure the geometrical path difference between the measured aspheric surface and the reference Fizeau surface independently for each pixel of the camera sensor.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!