scholarly journals A Palette of Efficient and Stable Far-Red and NIR Dye Lasers

2020 ◽  
Vol 10 (18) ◽  
pp. 6206
Author(s):  
Edurne Avellanal-Zaballa ◽  
Leire Gartzia-Rivero ◽  
Jorge Bañuelos ◽  
Inmaculada García-Moreno ◽  
Antonia R. Agarrabeitia ◽  
...  
Keyword(s):  
Spectral Region ◽  
Near Infrared ◽  
Laser Emission ◽  
Organic Dyes ◽  
Infrared Region ◽  
Dye Lasers ◽  
Spectral Window ◽  
Conformationally Restricted ◽  
The One ◽  
New Generation

The disposal of long-wavelength-emitting sources is of paramount relevance in technology and biophotonics due to the low interference with the surroundings that these kinds of far-red and near-infrared radiations hold. As a result of the continued efforts carried out during the last few years by our research group to design new boron-dipyrromethene (BODIPY) dyes with improved photonic performance, two approaches were tested to develop a new generation of organic dyes able to display efficient and long-lasting laser emission in both target spectral regions. On the one hand, the annulation of aromatic benzofuran at the dipyrrin backbone leads to conformationally restricted dyes yielding photostable and bright laser emission beyond 600 nm at the far-red spectral region. On the other hand, a more pronounced shift to longer wavelengths reaching 725 nm at the near-infrared region is feasible, while keeping a reasonably high laser efficiency and tolerance to prolonged and intense pumping, based on aza-BODIPYs bearing peripheral aryl rings. These two complementary strategies yield a library of laser-emitting compounds comprising the 600–725 nm spectral region. Moreover, their laser performance is better than the commercially available dye lasers active in this spectral window.

scholarly journals Stellar population study in early-type galaxies: an approach from the K band

2009 ◽  
Vol 5 (S262) ◽  
pp. 85-88
Author(s):  
Esther Mármol-Queraltó ◽  
Nicolás Cardiel ◽  
P. Sánchez-Blázquez ◽  
S. C. Trager ◽  
R. F. Peletier ◽  
...  
Keyword(s):  
Stellar Population ◽  
Near Infrared ◽  
Optical Measurements ◽  
Early Type ◽  
Spectral Window ◽  
Cluster Galaxies ◽  
Medium Resolution ◽  
Fornax Cluster ◽  
New Generation ◽  
K Band

AbstractA full understanding of the physical properties of integrated stellar systems demands a multiwavelength approach since each spectral window shows us the contribution of different types of stars. However, most of the observational effort in stellar population studies has been focused on the optical range. Now, the new generation of instruments allow us to explore the K band, where RGB and AGB stars dominate the light of the integrated spectra. Here we present a K-band spectroscopic analysis of early-type galaxies in different environments. Our sample comprises 12 field early-type galaxies observed with ISAAC at VLT with medium resolution, and they are compared with 11 Fornax cluster galaxies previously reported by Silva et al. (2008). The clear differences found in the infrared DCO and NaI indices between field and Fornax galaxies are discussed, trying to solve the puzzle formed by the near-infrared and optical measurements.

scholarly journals Surface Plasmon Resonances in Sn: In2O3 Thin Films with Diffraction Grating

Proceedings ◽  
2018 ◽  
Vol 2 (13) ◽  
pp. 1034
Author(s):  
Noriyuki Hasuike ◽  
Saito Ochiai ◽  
Ryotaro Iwakiri ◽  
Minoru Takeda ◽  
Woo Sik Yoo ◽  
...  
Keyword(s):  
Surface Plasmon ◽  
Spectral Region ◽  
Diffraction Grating ◽  
Near Infrared ◽  
Transparent Conductive Oxide ◽  
Infrared Region ◽  
Reflection Spectra ◽  
Surface Plasmon Resonances ◽  
Infrared Spectral Region ◽  
Infrared Spectral

We newly proposed transparent conductive oxide with diffraction grating structure as an excitation field of surface plasmon resonance working at near-infrared spectral region. We experimentally demonstrated the excitation of SPR using Sn-doped In2O3 films with micro-meter pitched diffraction grating. In this study, we considered the correlation between the grating pitch and the optical reflection spectra. Reflection spectra showed clear polarization properties in infrared spectral region, and the reflection edge has also correlation with the pitch of grating. From these results, the excitation of SPR grating was successfully demonstrated and the wavelength can be tuned by changing the grating pitch in infrared region.

scholarly journals A Straightforward Substitution Strategy to Tune BODIPY Dyes Spanning the Near-Infrared Region via Suzuki–Miyaura Cross-Coupling

Materials ◽  
2018 ◽  
Vol 11 (8) ◽  
pp. 1297 ◽  
Author(s):  
Guanglei Li ◽  
Yu Otsuka ◽  
Takuya Matsumiya ◽  
Toshiyuki Suzuki ◽  
Jianye Li ◽  
...  
Keyword(s):  
Near Infrared ◽  
Cross Coupling ◽  
Cumulus Cells ◽  
Infrared Region ◽  
Quantum Yields ◽  
Nir Dyes ◽  
Wide Range ◽  
One Step ◽  
The One ◽  
First Time

In this study, a series of new red and near-infrared (NIR) dyes derived from 4,4-difluoro-4-bora-3a,4a-diaza-s-indacene (BODIPY) were developed by introducing thiophene and its derivatives to the 3- and 5- positions of the dichloroBODIPY core. For the first time, cyclictriol boronates and N-methyliminodiacetic acid (MIDA) boronate were used as organoboron species to couple with 3,5-dichloroBODIPY via the one-step Suzuki–Miyaura cross-coupling. Six kinds of thieno-expended BODIPY dyes were synthesized in acceptable yields ranging from 31% to 79%. All six dyes showed different absorption and emission wavelengths spanning a wide range (c.a. 600–850 nm) in the red and NIR regions with relatively high quantum yields (19–85%). Cellular imaging of 8-(2,6-dimethylphenyl)-re3,5-di(2-thienyl)-BODIPY (dye 1) was conducted using bovine cumulus cells, and the fluorescence microscopy images indicated that the chromophore efficiently accumulated and was exclusively localized in the cytoplasm, suggesting it could be utilized as a subcellular probe. All six dyes were characterized using 1H-NMR and mass spectrometry.

Narrowband spectrally selective near-infrared photodetector based on up-conversion nanoparticles used in a 2D hybrid device

2017 ◽  
Vol 5 (7) ◽  
pp. 1591-1595 ◽  
Author(s):  
Nan Zhou ◽  
Bing Xu ◽  
Lin Gan ◽  
Junpei Zhang ◽  
Junbo Han ◽  
...  
Keyword(s):  
Near Infrared ◽  
Infrared Region ◽  
Infrared Photodetector ◽  
Device Structure ◽  
Spectral Window ◽  
Hybrid Device ◽  
Spectrally Selective ◽  
Near Infrared Region

A hybrid (NaYF4:Yb/Er@NaYF4:Nd/Yb)/MoS2 device structure is proposed to realize narrow spectral window photodetection in the near-infrared region.

Effects of Water on the Spectra of Model Compounds in the Short-Wavelength near Infrared Spectral Region (14,000–9091 cm−1 or 714–1100 nm)

1994 ◽  
Vol 2 (4) ◽  
pp. 199-212 ◽  
Author(s):  
James B. Reeves
Keyword(s):  
Spectral Region ◽  
Short Wavelength ◽  
Near Infrared ◽  
Wavelength Region ◽  
Infrared Region ◽  
Organic Liquids ◽  
Model Compounds ◽  
Water Solutions ◽  
Long Wavelength ◽  
Near Infrared Region

The spectral region from 14,000 to 9091 cm−1 (714–1100 nm) is increasingly being investigated for the analysis of high moisture systems due to its low absorption by water. The objective of this work was to determine if the effects of water on model compounds seen in the 7140–4000 cm−1 (1400–2500 nm) near infrared region occurred in this short wavelength region. Spectra were obtained by diffuse reflectance and transmission using a Fourier transform spectrometer. Spectra were obtained for a variety of organic liquids, liquid/water solutions, solids, wet solids and solutions of solids in water. Solutions included ethanol, acetic acid, acetone, pyridine, sugars, starch, cellulose, gums, amino acids and proteins. The spectral results showed that the effects seen in the 7140–4000 cm−1 (1400–2500 nm) region were also common in the 14,000–9091 cm−1 (714–1100 nm) region (i.e. peak shifts, loss of spectral features etc.). For example, in the long wavelength near infrared region, sugars, such as sucrose and glucose, were distinctively different as crystalline solids, but very similar in solution. In addition, molten glucose and urea appeared virtually identical to their dissolved counterparts indicating a loss of crystallinity to be the source of the changes. Finally, changes in the spectra of other materials, such as acetone, n-butylamine and ethanol (while similar in nature to those previously found in the near infrared) were not identical. Thus, while some shifts in peaks were found to occur with acetone/water mixtures, the dominant effects were changes in the relative intensities of peaks within the acetone spectrum, something not seen in the long wavelength region. Therefore, while the type of spectral effects caused by the presence of water may be similar across various spectral regions, the degree and exact nature of those effects vary with the material in question, the amount of water present and the region in question. Thus, the choice of the spectral region to be used for a specific problem should consider the materials in question, as well as other factors such as the usable pathlength.

Analysis of Cis and Trans 1,4 Contents of Polyisoprenes by Near Infrared Spectroscopy

1960 ◽  
Vol 33 (4) ◽  
pp. 975-981 ◽  
Author(s):  
P. J. Corish
Keyword(s):  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Infrared Region ◽  
New Method ◽  
Near Infrared Region ◽  
The One ◽  
Cis And Trans

Abstract A new method for the determination of cis and trans-1,4 units in synthetic polyisoprenes and gutta-rubber mixtures has been developed. The method uses the near infrared region of the spectrum and gives better, more reproducible results than the one using the normal infrared region.

Spinach Extract Derived Carbon Dots Decorated on ZnO Nanorods for Photocatalytic Dye Degradation

2021 ◽  
Vol 13 (5) ◽  
pp. 922-926
Author(s):  
Sia Won ◽  
Jong-Sung Kim
Keyword(s):  
Carbon Dots ◽  
Near Infrared ◽  
Organic Dyes ◽  
Dye Degradation ◽  
Zno Nanorods ◽  
Infrared Region ◽  
Blue Dye ◽  
Analytical Instruments ◽  
First Order Kinetics ◽  
Spinach Extract

The carcinogenic and mutagenic nature of organic dyes makes their removal from dye-containing wastewaters essential prior to the discharge of such wastewaters. We synthesized carbon dots having emission wavelengths in the near-infrared region from spinach extract. Thereafter, CDs were embedded on ZnO nanorods through hydrothermal treatment. The prepared ZnO doped with CDs were characterized by various analytical instruments and used to photocatalytically degrade methylene blue dye under sunlight. The as-prepared ZnO exhibited nanorod morphology, with the CDs doped on its surface. The dye degradation followed pseudo-first-order kinetics; the ZnO doped with CDs synthesized at pH 10 achieved the highest dye degradation, with a kinetic coefficient of 0.02889 min−1. This study shows that the photocatalytic efficiency of ZnO can be effectively improved by doping with CDs.

scholarly journals Chromospheres, Coronae and Mass Loss in Solar and Late-Type Stars

1980 ◽  
Vol 5 ◽  
pp. 533-540
Author(s):  
Carole Jordan
Keyword(s):  
Mass Loss ◽  
Spectral Region ◽  
Near Infrared ◽  
Infrared Region ◽  
Late Type ◽  
Near Infrared Region

Until observations in the EUV spectral region became available the existence of hot extended envelopes aroung latetype stars was inferred from the presence of visible and near infrared region lines which cannot be formed in radiative equilibrium within the stellar photospheres. The traditional indicators of stellar chromospheres have been the Ca II H and K lines, particularly the presence of emission components, the He I 10830 A triplet, the He II 4686 A line and emission in various hydrogen Balmer and Paschen lines. When observations from rockets and satellites become possible the strong lines of Mg II at 2800 A and the H Lya line at 1216 A could also be included in the modelling of stellar chromospheres. The new spectra from IUE allow not only stellar chromospheres to be studied but also stellar transition regions, should hot coronae exist.

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