scholarly journals Ge2Sb2Se4Te1-based multifunctional metalenses for polarization-independent, switchable and dual-mode focusing in the mid-infrared region

2021 ◽  
Author(s):  
Jun Xu ◽  
Xi Tian ◽  
Pei Ding ◽  
Kun Xu ◽  
Zhiyuan Li
Keyword(s):  
Infrared Region ◽  
Dual Mode ◽  
Mid Infrared ◽  
Polarization Independent

Polarization-independent broadband achromatic metalens in the mid-infrared (3-5 μm) region

2021 ◽  
Author(s):  
Wenhui Xiong ◽  
Chenchen Sha ◽  
Jianping Ding
Keyword(s):  
Numerical Simulation ◽  
Infrared Imaging ◽  
Chromatic Aberration ◽  
Infrared Region ◽  
Mid Infrared ◽  
Light Manipulation ◽  
Wavefront Shaping ◽  
Polarization Independent

Abstract With superior capabilities for light manipulation and wavefront shaping, the metasurface recently has caught growing attention. However, the presence of chromatic aberration hinders metasurfaces, especially metalenses, from wider applications. Here, we design a polarization-independent broadband achromatic focusing metalens in the mid-infrared region, which covers continuous bands in 3-5 μm. Numerical simulation shows that different wavelengths can be focused to the same plane with a nearly diffraction-limited resolution, and can achieve an average focusing efficiency of nearly 70% in the whole bandwidth. We expect that our approach can underpin the development of integrated and mid-infrared imaging and detection.

Mid and near Infrared Study of Carbohydrates by Canonical Correlation Analysis

1993 ◽  
Vol 1 (2) ◽  
pp. 99-108 ◽  
Author(s):  
P. Robert ◽  
M.F. Devaux ◽  
A. Qannari ◽  
M. Safar
Keyword(s):  
Correlation Analysis ◽  
Infrared Spectra ◽  
Canonical Correlation ◽  
Near Infrared ◽  
Sugar Content ◽  
Infrared Region ◽  
Total Sugar ◽  
Mid Infrared ◽  
Total Sugar Content ◽  
Near Infrared Spectra

Multivariate data treatments were applied to mid and near infrared spectra of glucose, fructose and sucrose solutions in order to specify near infrared frequencies that characterise each carbohydrate. As a first step, the mid and near infrared regions were separately studied by performing Principal Component Analyses. While glucose, fructose and sucrose could be clearly identified on the similarity maps derived from the mid infrared spectra, only the total sugar content of the solutions was observed when using the near infrared region. Characteristic wavelengths of the total sugar content were found at 2118, 2270 and 2324 nm. In a second step, the mid and near infrared regions were jointly studied by a Canonical Correlation Analysis. As the assignments of frequencies are generally well known in the mid infrared region, it should be useful to study the relationships between the two infrared regions. Thus, the canonical patterns obtained from the near infrared spectra revealed wavelengths that characterised each carbohydrate. The OH and CH combination bands were observed at: 2088 and 2332 nm for glucose, 2134 and 2252 nm for fructose, 2058 and 2278 nm for sucrose. Although a precise assignment of the near infrared bands to chemical groups within the molecules was not possible, the present work showed that near infrared spectra of carbohydrates presented specific features.

Ortho-deuterium Raman laser using the S/sub 0/(2) rotational transition in the mid-infrared region

1997 ◽  
Vol 33 (12) ◽  
pp. 2174-2177 ◽  
Author(s):  
T. Takasaki ◽  
A. Suda ◽  
K. Sato ◽  
T. Shinozaki ◽  
K. Nagasaka ◽  
...  
Keyword(s):  
Raman Laser ◽  
Infrared Region ◽  
Rotational Transition ◽  
Mid Infrared

Microstructure and thermal stability of amorphous materials in the GeS2−La2S3 system

1991 ◽  
Vol 6 (12) ◽  
pp. 2694-2700 ◽  
Author(s):  
Prashant N. Kumta ◽  
Subhash H. Risbud
Keyword(s):  
Thermal Stability ◽  
Amorphous Materials ◽  
Fiber Optic ◽  
Molecular Level ◽  
Infrared Region ◽  
Mid Infrared ◽  
Heat Treated ◽  
Stable Glasses ◽  
Microstructural Studies ◽  
Thermal Stability Of

GeS2 is known to be a good chalcogenide glass former with a transmission cutoff at 11 μm and has been studied for fiber optic application in the mid infrared region. The rare earth sulfides, oxysulfides, and oxides (La–Er) form reasonably good and stable glasses when mixed with chalcogenides such as Ga2S3. In this work, glass formation was studied in the GeS2−La2S3 system. Two compositions containing 60 mol % and 92.5 mol % GeS2, respectively, were analyzed, and the effects of composition on the microstructure and thermal stability of these glasses were investigated. Microstructural studies were conducted on the as-prepared and heat-treated glasses using TEM and SEM/EDXA. Glasses rich in GeS2 exhibited primary (6–88 nm) and secondary (3–13 nm) phase separation at the molecular level. Differential thermal analysis performed on these glasses indicated glass transition temperatures (Tg) of 510 °C and 420 °C for the two compositions studied. The glasses were stable and the (Tg) was observed to decrease with increasing contents of GeS2 in these glasses.

scholarly journals FTIR Spectrophotometry as a Green Tool for Quantitative Analysis of Drugs: Practical Application to Amoxicillin

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Stefany Fanelli ◽  
Alexander Zimmermann ◽  
Eliane Gandolpho Totóli ◽  
Hérida Regina Nunes Salgado
Keyword(s):  
Environmentally Friendly ◽  
Infrared Region ◽  
Potassium Bromide ◽  
Bactericidal Action ◽  
Practical Application ◽  
Mid Infrared ◽  
Brazilian Legislation ◽  
Ich Guidelines ◽  
Ftir Spectrophotometry ◽  
Environmentally Friendly Method

Amoxicillin is an antimicrobial agent that belongs to the penicillin compounds. Its bactericidal action causes a destruction of the cell wall of bacteria. It is widely used in clinical practice, and it belongs to the Brazilian National List of Essential Drugs (RENAME). In literature, there are some green analytical methods for the amoxicillin analysis; however, none of them is focused on its quantification in capsules. Therefore, the aim of this study was to validate an environmentally friendly analytical method for the analysis of this antimicrobial action in capsules, using spectrophotometry in the mid-infrared region. The analyses were performed in the spectral range of 1815–1736 cm−1, and the samples were analyzed as potassium bromide pellets. The method was validated according to the ICH guidelines and Brazilian legislation. Linearity, selectivity, precision, accuracy, and robustness were evaluated and showed adequate results for method validation, in a concentration range of 0.5–1.5 mg/pellet. Thus, it is concluded that the validated spectrophotometric method is able to quantify amoxicillin in capsules. In addition, it is a fast, economical, and environmentally friendly method, since it does not use organic solvents, and it can be used for quality control of routine analysis of this drug.

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