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The WFIRST-AFTA 2.4 m telescope will provide in the next decade the opportunity to host a coronagraph for the imaging and spectroscopy of planets and disks. The telescope, however, is not ideal, given its obscured aperture. Only recently…

Instrumentation and Methods for Astrophysics · Physics 2015-09-18 John Krist , Bijan Nemati , Bertrand Mennesson

The Exo-Planet Imaging Camera and Spectrograph (EPICS) for the future 42-meter European-Extremely Large Telescope, will enable direct images, and spectra for both young and old Jupiter-mass planets in the infrared. To achieve the required…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 P. Martinez , C. Dorrer , M. Kasper

In this paper we study and design quasi-2D optomechanical crystals, waveguides, and resonant cavities formed from patterned slabs. Two-dimensional periodicity allows for in-plane pseudo-bandgaps in frequency where resonant optical and…

Optics · Physics 2010-11-23 Amir H. Safavi-Naeini , Oskar Painter

Nanochannels with high width-to-height aspect ratios are desirable for many applications, particularly those requiring optical access, but remain challenging to fabricate. In this work, the direct laser writing of such channels between…

Liquid-crystal devices (LCDs) offer a potential route toward adaptive optical components for use in the < 2 THz band of the electromagnetic spectrum. We demonstrate LCDs using a commercially available material (E7), with unbiased…

We developed a microdisplay-based microscope projection photolithography (MDMPP) technique in which a liquid crystal (LC) microdisplay is used as a reconfigurable photomask for a microscope projector. The LC microdisplay provides a…

Physics Education · Physics 2022-03-23 Young-Gu Ju , Hyeon-Jun Kim , Young-Min Ko

In recent years, phase mask coronagraphy has become increasingly efficient in imaging the close environment of stars, enabling the search for exoplanets and circumstellar disks. Coronagraphs are ideally suited instruments, characterized by…

Instrumentation and Methods for Astrophysics · Physics 2014-12-02 Christian Delacroix , Oliver Absil , Dimitri Mawet , Charles Hanot , Mikael Karlsson , Pontus Forsberg , Eric Pantin , Jean Surdej , Serge Habraken

Direct imaging of exoplanets or circumstellar disk material requires extreme contrast at the 10-6 to 10-12 levels at < 100 mas angular separation from the star. Focal-plane mask (FPM) coronagraphic imaging has played a key role in this…

Instrumentation and Methods for Astrophysics · Physics 2017-07-12 Jonas Kühn , Patapis Polychronis , Garreth Ruane , Xin Lu

The inkjet-fabricated liquid crystal (LC) droplet device not only capitalizes on the intrinsic birefringence properties of liquid crystals but also leverages the hemispherical shape of droplet devices on substrates. This configuration…

Recently, a silicon micromachining method to produce tetrahedral silicon particles was discovered. In this report we determine, using band structure calculations, the optical properties of diamond-lattice photonic crystals when assembled…

Optics · Physics 2011-08-26 Léon A. Woldering , Leon Abelmann , Miko C. Elwenspoek

We report on a soft route towards optical vortex coronagraphy based on self-engineered electrically tunable vortex masks based on liquid crystal topological defects. These results suggest that a nature-assisted technological approach to the…

Optics · Physics 2016-11-17 Artur Aleksanyan , Etienne Brasselet

Two-dimensional crystals, single sheets of layered materials, often show distinct properties desired for optoelectronic applications, such as larger and direct band gaps, valley- and spinorbit effects. Being atomically thin, the low amount…

Materials Science · Physics 2018-11-14 Roman Kempt , Agnieszka Kuc , Jae Hyo Han , Jinwoo Cheon , Thomas Heine

The detection and characterization of Earth-like exoplanets around Sun-like stars for future flagship missions requires coronagraphs to achieve contrasts on the order of 1e-10 at close angular separations and over large spectral bandwidths…

Instrumentation and Methods for Astrophysics · Physics 2022-12-07 Niyati Desai , Jorge Llop-Sayson , Arielle Bertrou-Cantou , Garreth Ruane , A. J. Eldorado Riggs , Eugene Serabyn , Dimitri Mawet

The detection of molecular species in the atmospheres of earth-like exoplanets orbiting nearby stars requires an optical system that suppresses starlight and maximizes the sensitivity to the weak planet signals at small angular separations.…

Instrumentation and Methods for Astrophysics · Physics 2017-08-22 Garreth Ruane , Dimitri Mawet , Jeffrey Jewell , Stuart Shaklan

Current wireless systems are experiencing unprecedented pressure that could be relieved by shifting carrier frequencies towards the terahertz spectrum. Yet, components are required to enable spectrally efficient communications at such high…

Optics · Physics 2021-09-24 Hichem Guerboukha , Jingwen Li

We demonstrate two-dimensional photonic crystal cavities operating at telecommunication wavelengths in a single-crystal diamond membrane. We use a high-optical-quality and thin (~ 300 nm) diamond membrane, supported by a polycrystalline…

Despite promising astrometric signals, to date there has been no success in direct imaging of a hypothesized third member of the Sirius system. Using the Clio instrument and MagAO adaptive optics system on the Magellan Clay 6.5 m telescope,…

Subwavelength grating micro-polarizer arrays, as a type of focal plane division simultaneous detection method, are significantly advancing the development and practical application of polarization imaging technology. Based on the…

Optics · Physics 2024-10-17 Tianshi Lu , Fuyuan Deng , Yufeng Wei , Zhipeng Zeng , Xinghui Li

Achieving the Habitable Worlds Observatory (HWO) goal of 10^-10 contrast at a separation of 3 $\lambda$/D across a 20% bandwidth requires coronagraph focal plane masks with both broadband high contrast performance and high planet…

Instrumentation and Methods for Astrophysics · Physics 2026-04-01 Niyati Desai , Garreth Ruane , Susan Redmond , Dimitri Mawet , Eugene Serabyn , Bertrand Mennesson

Context. The Annular Groove Phase Mask (AGPM) is one possible implementation of the vector vortex coronagraph, where the helical phase ramp is produced by a concentric subwavelength grating. For several years, we have been manufacturing…