scholarly journals Photosensors: A Retina-Like Dual Band Organic Photosensor Array for Filter-Free Near-Infrared-to-Memory Operations (Adv. Mater. 32/2017)

2017 ◽  
Vol 29 (32) ◽  
Author(s):  
Hanlin Wang ◽  
Hongtao Liu ◽  
Qiang Zhao ◽  
Zhenjie Ni ◽  
Ye Zou ◽  
...  
Keyword(s):  
Near Infrared ◽  
Dual Band

scholarly journals Ultraviolet and Near‐Infrared Dual‐Band Selective‐Harvesting Transparent Luminescent Solar Concentrators

2021 ◽  
Vol 11 (12) ◽  
pp. 2003581
Author(s):  
Chenchen Yang ◽  
Wei Sheng ◽  
Mehdi Moemeni ◽  
Matthew Bates ◽  
Christopher K. Herrera ◽  
...  
Keyword(s):  
Near Infrared ◽  
Dual Band ◽  
Solar Concentrators ◽  
Selective Harvesting ◽  
Luminescent Solar Concentrators

scholarly journals Investigating the young solar system analog HD 95086

2018 ◽  
Vol 617 ◽  
pp. A76 ◽  
Author(s):  
G. Chauvin ◽  
R. Gratton ◽  
M. Bonnefoy ◽  
A.-M. Lagrange ◽  
J. de Boer ◽  
...  
Keyword(s):  
Radial Velocity ◽  
Near Infrared ◽  
Scattered Light ◽  
Spectral Energy Distribution ◽  
Giant Planet ◽  
Giant Planets ◽  
Dual Band ◽  
Spectral Energy ◽  
Semi Major Axis ◽  
Integral Field Spectrograph

Context. HD 95086 (A8V, 17 Myr) hosts a rare planetary system for which a multi-belt debris disk and a giant planet of 4–5 MJup have been directly imaged. Aims. Our study aims to characterize the global architecture of this young system using the combination of radial velocity and direct imaging observations. We want to characterize the physical and orbital properties of HD 95086 b, search for additional planets at short and wide orbits and image the cold outer debris belt in scattered light. Methods. We used HARPS at the ESO 3.6 m telescope to monitor the radial velocity of HD 95086 over two years and investigate the existence of giant planets at less than 3 au orbital distance. With the IRDIS dual-band imager and the IFS integral field spectrograph of SPHERE at VLT, we imaged the faint circumstellar environment beyond 10 au at six epochs between 2015 and 2017. Results. We do not detect additional giant planets around HD 95086. We identify the nature (bound companion or background contaminant) of all point-like sources detected in the IRDIS field of view. None of them correspond to the ones recently discovered near the edge of the cold outer belt by ALMA. HD 95086 b is resolved for the first time in J-band with IFS. Its near-infrared spectral energy distribution is well fitted by a few dusty and/or young L7–L9 dwarf spectral templates. The extremely red 1–4 μm spectral distribution is typical of low-gravity objects at the L/T spectral type transition. The planet’s orbital motion is resolved between January 2015 and May 2017. Together with past NaCo measurements properly re-calibrated, our orbital fitting solutions favor a retrograde low to moderate-eccentricity orbit e = 0.2+0.3−0.2, with a semi-major axis ~52 au corresponding to orbital periods of ~288 yr and an inclination that peaks at i = 141°, which is compatible with a planet-disk coplanar configuration. Finally, we report the detection in polarimetric differential imaging of the cold outer debris belt between 100 and 300 au, consistent in radial extent with recent ALMA 1.3 mm resolved observations.

scholarly journals Perfect Dual-Band Absorber Based on Plasmonic Effect with the Cross-Hair/Nanorod Combination

Nanomaterials ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 493 ◽  
Author(s):  
Yuan-Fong Chou Chau ◽  
Chung-Ting Chou Chao ◽  
Hung Ji Huang ◽  
Muhammad Raziq Rahimi Kooh ◽  
N. T. R. N. Kumara ◽  
...  
Keyword(s):  
Figure Of Merit ◽  
Near Infrared ◽  
High Sensitivity ◽  
Dual Band ◽  
Localized Surface Plasmon ◽  
Perfect Absorber ◽  
Plasmonic Effect ◽  
Plasmonic Sensor ◽  
Nanophotonic Devices ◽  
The Cross

Plasmonic effect using a cross-hair can convey strongly localized surface plasmon modes among the separated composite nanostructures. Compared to its counterpart without the cross-hair, this characteristic has the remarkable merit of enhancing absorptance at resonance and can make the structure carry out a dual-band plasmonic perfect absorber (PPA). In this paper, we propose and design a novel dual-band PPA with a gathering of four metal-shell nanorods using a cross-hair operating at visible and near-infrared regions. Two absorptance peaks at 1050 nm and 750 nm with maximal absorptance of 99.59% and 99.89% for modes 1 and 2, respectively, are detected. High sensitivity of 1200 nm refractive unit (1/RIU), figure of merit of 26.67 and Q factor of 23.33 are acquired, which are very remarkable compared with the other PPAs. In addition, the absorptance in mode 1 is about nine times compared to its counterpart without the cross-hair. The proposed structure gives a novel inspiration for the design of a tunable dual-band PPA, which can be exploited for plasmonic sensor and other nanophotonic devices.

scholarly journals First scattered light detection of a nearly edge-on transition disk around the T Tauri star RY Lupi

2018 ◽  
Vol 614 ◽  
pp. A88 ◽  
Author(s):  
M. Langlois ◽  
A. Pohl ◽  
A.-M. Lagrange ◽  
A.- L. Maire ◽  
D. Mesa ◽  
...  
Keyword(s):  
Adaptive Optics ◽  
Near Infrared ◽  
Planet Formation ◽  
Scattered Light ◽  
Emission Feature ◽  
Point Sources ◽  
Tauri Star ◽  
Dual Band ◽  
High Angular Resolution ◽  
T Tauri

Context. Transition disks are considered sites of ongoing planet formation, and their dust and gas distributions could be signposts of embedded planets. The transition disk around the T Tauri star RY Lup has an inner dust cavity and displays a strong silicate emission feature. Aims. Using high-resolution imaging we study the disk geometry, including non-axisymmetric features, and its surface dust grain, to gain a better understanding of the disk evolutionary process. Moreover, we search for companion candidates, possibly connected to the disk. Methods. We obtained high-contrast and high angular resolution data in the near-infrared with the VLT/SPHERE extreme adaptive optics instrument whose goal is to study the planet formation by detecting and characterizing these planets and their formation environments through direct imaging. We performed polarimetric imaging of the RY Lup disk with IRDIS (at 1.6 μm), and obtained intensity images with the IRDIS dual-band imaging camera simultaneously with the IFS spectro-imager (0.9–1.3 μm). Results. We resolved for the first time the scattered light from the nearly edge-on circumstellar disk around RY Lup, at projected separations in the 100 au range. The shape of the disk and its sharp features are clearly detectable at wavelengths ranging from 0.9 to 1.6 μm. We show that the observed morphology can be interpreted as spiral arms in the disk. This interpretation is supported by in-depth numerical simulations. We also demonstrate that these features can be produced by one planet interacting with the disk. We also detect several point sources which are classified as probable background objects.

scholarly journals Giant dual-band asymmetric transmission based on all-dielectric metamaterial in the near-infrared band

2021 ◽  
Author(s):  
BingYu Chen ◽  
Kun Zhang ◽  
Qun Xie ◽  
Xingrun Zhang ◽  
Lijun Guo ◽  
...  
Keyword(s):  
Near Infrared ◽  
Dual Band ◽  
Infrared Band ◽  
Asymmetric Transmission

scholarly journals New spectro-photometric characterization of the substellar object HR 2562 B using SPHERE

2018 ◽  
Vol 612 ◽  
pp. A92 ◽  
Author(s):  
D. Mesa ◽  
J.-L. Baudino ◽  
B. Charnay ◽  
V. D’Orazi ◽  
S. Desidera ◽  
...  
Keyword(s):  
Near Infrared ◽  
Speckle Noise ◽  
Dual Band ◽  
Physical Parameters ◽  
Atmospheric Models ◽  
Fundamental Properties ◽  
Spectral Bands ◽  
Very Large Telescope ◽  
Integral Field Spectrograph

Aims. HR 2562 is an F5V star located at ~33 pc from the Sun hosting a substellar companion that was discovered using the Gemini planet imager (GPI) instrument. The main objective of the present paper is to provide an extensive characterization of the substellar companion, by deriving its fundamental properties. Methods. We observed HR 2562 with the near-infrared branch composed by the integral field spectrograph (IFS) and the infrared dual band spectrograph (IRDIS) of the spectro-polarimetric high-contrast exoplanet research (SPHERE) instrument at the very large telescope (VLT). During our observations IFS was operating in the Y J band, while IRDIS was observing with the H broadband filter. The data were reduced with the dedicated SPHERE GTO pipeline, which is custom designed for this instrument. On the reduced images, we then applied the post-processing procedures that are specifically prepared to subtract the speckle noise. Results. The companion is clearly detected in both IRDIS and IFS datasets. We obtained photometry in three different spectral bands. The comparison with template spectra allowed us to derive a spectral type of T2–T3 for the companion. Using both evolutionary and atmospheric models we inferred the main physical parameters of the companion obtaining a mass of 32 ± 14 MJup, Teff = 1100 ± 200 K, and log g = 4.75 ± 0.41.

Dual-band graphene-induced plasmonic quarter-wave plate metasurface in the near infrared

2017 ◽  
Vol 123 (8) ◽  
Author(s):  
Edgar Owiti ◽  
Hanning Yang ◽  
Calvine Ominde ◽  
Xiudong Sun
Keyword(s):  
Near Infrared ◽  
Dual Band ◽  
Quarter Wave Plate ◽  
Wave Plate ◽  
Quarter Wave

scholarly journals Ultra Narrow Dual-Band Perfect Absorber Based on a Dielectric−Dielectric−Metal Three-Layer Film Material

Micromachines ◽  
2021 ◽  
Vol 12 (12) ◽  
pp. 1552
Author(s):  
Bin Liu ◽  
Pinghui Wu ◽  
Hongyang Zhu ◽  
Li Lv
Keyword(s):  
Plasmon Resonance ◽  
Near Infrared ◽  
Incident Angle ◽  
Structural Parameters ◽  
Dual Band ◽  
Refractive Index Sensor ◽  
Perfect Absorber ◽  
Film Material ◽  
High Q ◽  
Magnetic Polaritons

This paper proposes a perfect metamaterial absorber based on a dielectric−dielectric−metal structure, which realizes ultra-narrowband dual-band absorption in the near-infrared band. The maximum Q factor is 484. The physical mechanism that causes resonance is hybrid coupling between magnetic polaritons resonance and plasmon resonance. At the same time, the research results show that the intensity of magnetic polaritons resonance is much greater than the intensity of the plasmon resonance. By changing the structural parameters and the incident angle of the light source, it is proven that the absorber is tunable, and the working angle tolerance is 15°. In addition, the sensitivity and figure of merit when used as a refractive index sensor are also analyzed. This design provides a new idea for the design of high-Q optical devices, which can be applied to photon detection, spectral sensing, and other high-Q multispectral fields.

scholarly journals AUTOMATIZING DEGRADATION MAPPING OF ANCIENT STELAE BY DUAL-BAND IMAGING AND MACHINE LEARNING-BASED CLASSIFICATION

2021 ◽  
Vol VIII-M-1-2021 ◽  
pp. 9-16
Author(s):  
E. Adamopoulos ◽  
F. Rinaudo ◽  
D. Adamopoulou
Keyword(s):  
Machine Learning ◽  
Image Segmentation ◽  
Environmental Factors ◽  
Digital Image ◽  
Near Infrared ◽  
Infrared Imaging ◽  
Biological Agents ◽  
Dual Band ◽  
Classification Methods ◽  
Near Infrared Imaging

Abstract. Degradation patterns are the visible consequence of the impacts of environmental factors and biological agents on stone heritage. Accurately documenting them is a key requisite when studying exposed stone antiquities to interpret weathering causes, identify conservation needs, and plan cleaning interventions. However, a significant gap can be identified in practical automatized procedures for mapping patterns on stone antiquities, such as ancient stelae. This work evaluates a workflow that uses visible and near-infrared imaging, combined with machine learning-based digital image segmentation tools, to classify degradation patterns on marble stelae correctly and cost-effectively. For this work, different classification methods are considered. Results are analyzed using error matrixes and reference degradation maps. The application cases include stelae displayed in the courtyard of the Archaeological Museum of Eretria (Euboea, Greece). The proposed methodology aims at being easily adapted to facilitate the conservators’ work.

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