Related papers: New method to achieve the proper polarization stat…
We demonstrate a pump-probe scheme in which an atomic vapor is optically pumped with circularly polarized light and probed with a vector vortex beam. The pump induces a macroscopic magnetization in the medium, which gives rise to…
We present a novel system to calibrate millimeter-wave polarimeters for CMB polarization measurements. This technique is an extension of the conventional metal mirror rotation approach, however it employs cryogenically-cooled blackbody…
Small-scale vortices in the solar photosphere play a central role in transporting mass, energy, and momentum into the upper solar atmosphere, yet reliably detecting these structures remains rather challenging. We address this problem by…
One of the major science goals of the Visible Emission Line Coronagraph (VELC) payload aboard the Aditya-L1 mission is to map the coronal magnetic field topology and the quantitative estimation of longitudinal magnetic field on routine…
Wavefront shaping has revolutionized imaging deep in scattering media, being able to spatially and temporally refocus light through or inside the medium. However, wavefront shaping is not compatible yet with polarization-resolved microscopy…
Broadband-tunable sources of circularly-polarized light are crucial in fields such as laser science, biomedicine and spectroscopy. Conventional sources rely on nonlinear wavelength conversion and polarization control using standard optical…
High contrast imaging using coronagraphy is one of the main avenues to enable the search for life on extrasolar Earth analogs. The HiCAT testbed aims to demonstrate coronagraphy and wavefront control for segmented on-axis space telescopes…
The raw coronagraphic performance of current high-contrast imaging instruments is limited by the presence of a quasi-static speckle (QSS) background, resulting from instrumental non-common path errors (NCPEs). Rapid development of efficient…
Direct detection of exoplanets requires high dynamic range imaging. Coronagraphs could be the solution, but their performance in space is limited by wavefront errors (manufacturing errors on optics, temperature variations, etc.), which…
Photons may have homogeneous polarization and may carry quantized orbital angular momentum (OAM). Photon entanglement has been realized in various degrees of freedom such as polarization and OAM. Using a pair of orthogonally polarized…
Vortices are topological objects carrying quantized orbital angular momentum and have been widely studied in many physical systems for their applicability in information storage and processing. In systems with spin degree of freedom the…
Using an l = 1 blazed fork-hologram at the focal plane of the Asiago 122 cm telescope, we obtained optical vortices from the stellar system Rasalgethi (alpha Herculis) and from the single star Arcturus (alpha Bootis). We have analyzed the…
The development of spaceborne coronagraphic technology is of paramount importance to the detection of habitable exoplanets in visible light. In space, coronagraphs are able to bypass the limitations imposed by the atmosphere to reach deeper…
Optical vortex and vector field are two important types of structured optical fields. Due to their wide applications and unique features in many scientific realms, the generation, manipulation and measurement of such fields have attracted…
The problem of imaging materials with circular polarization properties is discussed within the framework of vectorial ptychography. We demonstrate, both theoretically and numerically, that using linear polarizations to investigate such…
We show that the polarization state of coherent light propagating through an optically thick multiple-scattering medium, can be controlled by wavefront shaping, i.e. by controlling only the spatial phase of the incoming field with a spatial…
We conducted a number of multi-band coronagraph experiments using a vacuum chamber and a binary-shaped pupil mask which in principle should work at all wavelengths, in the context of the research and development on a coronagraph to observe…
Imaging terrestrial exoplanets around nearby stars is a formidable technical challenge, requiring the development of coronagraphs to suppress the stellar halo of diffracted light at the location of the planet. In this review, we derive the…
A white light vortex coronagraph was used to experimentally achieve sub-resolution detection. The angular location of the centroid, $\gamma$, and the angular extent of circular pinhole sources, $\Theta$, were measured to within errors of…
Holography is a cornerstone characterisation and imaging technique that can be applied to the full electromagnetic spectrum, from X-rays to radio waves or even particles such as neutrons. The key property in all these holographic approaches…