Optical Transport Network

Optical Transmission and Networks for Next Generation Internet Traffic Highways ◽

10.4018/978-1-4666-6575-0.ch002 ◽

2015 ◽

pp. 28-58

Keyword(s):

Refractive Index ◽

Nonlinear Refractive Index ◽

Power Level ◽

Nonlinear Effects ◽

Optical Signal ◽

Stimulated Scattering ◽

Optical Signals ◽

Optical Transport Network ◽

Scattering Effects

The purpose of this chapter is to discuss two major categories of nonlinear effects related either to nonlinear refractive index or to nonlinear stimulated scattering effects. The effects related to nonlinear refractive index occur due to the dependence of the refractive index on the optical signal intensity. On the other hand, stimulated scattering effects are caused by interaction between light and material. As many wavelength signal channels travel through the optical fiber, they encounter many of those nonlinear effects impairments that affect the signal power level and hence degrade sharply the quality of the signal resulting in interference among signals carried by different wavelength channels. Therefore, before delving into the optical transmission performance issues, a physical picture of how optical signals behave in the presence of the most important nonlinear effect impairments is drawn.

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The Optical Signal-to-Crosstalk Ratio for the MBA(N, e, g) Switching Fabric †

Sensors ◽

10.3390/s21041534 ◽

2021 ◽

Vol 21 (4) ◽

pp. 1534

Author(s):

Remigiusz Rajewski

Keyword(s):

Optical Switching ◽

Essential Feature ◽

Optical Signal ◽

Point Of View ◽

Signal Quality ◽

Switching Networks ◽

Optical Elements ◽

Optical Signals ◽

Switching Fabric

The banyan-type switching networks, well known in switching theory and called the logdN switching fabrics, are composed of symmetrical switching elements of size d×d. In turn, the modified baseline architecture, called the MBA(N,e,g), is only partially built from symmetrical optical switching elements, and it is constructed mostly from asymmetrical optical switching elements. Recently, it was shown that the MBA(N,e,g) structure requires a lower number of passive as well as active optical elements than the banyan-type switching fabric of the same capacity and functionality, which makes it an attractive solution. However, the optical signal-to-crosstalk ratio for the MBA(N,e,g) was not investigated before. Therefore, in this paper, the optical signal-to-crosstalk ratio in the MBA(N,e,g) was determined. Such crosstalk influences the output signal’s quality. Thus, if such crosstalk is lower, the signal quality is better. The switching fabric proposed in the author’s previous work has lower optical signal losses than a typical Beneš and banyan-type switching networks of this same capacity and functionality, which gives better quality of transmitted optical signals at the switching node’s output. The investigated MBA(N,e,g) architecture also contains one stage fewer than banyan-type network of the same capacity, which is an essential feature from the optical switching point of view.

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NON-LINEAR REFRACTIVE INDEX MEASUREMENT OF (2E)-3-[4-(DIMETHYLAMINO)PHENYL]-1-(2,5-DIMETHYLTHIOPHEN-3-YL)PROP-2-EN-1-ONE AND (2E)-3-(3,4-DIMETHOXYPHENYL)-1-(2,5-DIMETHYLTHIOPHEN-3-YL)PROP-2-EN-1-ONE

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863511006005 ◽

2011 ◽

Vol 20 (02) ◽

pp. 183-191 ◽

Cited By ~ 3

Author(s):

FRYAD Z. HENARI ◽

ABDULLAH M. ASIRI

Keyword(s):

Refractive Index ◽

Absorption Coefficient ◽

Nonlinear Absorption ◽

Nonlinear Refractive Index ◽

Continuous Wave ◽

Nonlinear Effects ◽

Optical Limiting ◽

Nonlinear Absorption Coefficient ◽

Refractive Index Measurement ◽

Index Measurement

We report results from investigations of the nonlinear refractive index and nonlinear absorption coefficient of (2E)-3-[4-(Dimethylamino)phenyl]-1-(2,5-dimethylthiophen-3-yl)prop-2-en-1-one and (2E)-3-(3,4-Dimethoxyphenyl)-1-(2,5-dimethylthiophen-3-yl) prop-2-en-1-one using Z-scan technique with a continuous wave (cw) laser at wavelengths 488 nm and 514 nm. The nonlinear refractive index and nonlinear absorption coefficient of both samples were evaluated. The origin of the nonlinear effects was discussed. Optical limiting based on light induced nonlinear refractive index variation is demonstrated. The limiting thresholds were estimated for both samples. The results suggested that these materials offer promise as candidates for optical limiting and optical devices in the low power regime.

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NONLINEAR EFFECTS IN ERBIUM-DOPED FIBRES

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218199193000243 ◽

1993 ◽

Vol 02 (03) ◽

pp. 401-413 ◽

Cited By ~ 3

Author(s):

P.L. CHU ◽

Y.L. XUE

Keyword(s):

Refractive Index ◽

Excited State ◽

Transient Response ◽

Ground State ◽

Nonlinear Refractive Index ◽

Nonlinear Effects ◽

Experimental Investigations ◽

Signal Power ◽

Switching Speed ◽

Erbium Doped

Theoretical and experimental investigations of the nonlinear refractive index in an Erbium-doped fibre is presented. The transient response of this fibre is also examined. The switching speed can be improved by using a signal power at a wavelength close to the resonant wavelength between the excited state and the ground state.

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Ag Nanoparticles: Experimental Study of Sign Identification of Nonlinear Refractive Index by Moiré Deflectometry and Z-Scan Methods

ISRN Nanomaterials ◽

10.1155/2013/327575 ◽

2013 ◽

Vol 2013 ◽

pp. 1-6 ◽

Cited By ~ 1

Author(s):

Adeleh Granmayeh Rad ◽

Khosro Madanipour ◽

Ata Koohian

Keyword(s):

Refractive Index ◽

Ag Nanoparticles ◽

Nonlinear Refractive Index ◽

Second Harmonic ◽

Pure Water ◽

Nonlinear Effects ◽

Probe Laser ◽

Beam Power ◽

Moiré Fringes ◽

Moiré Deflectometry

Two different methods are presented for the sign identification of nonlinear refractive index () of Ag colloidal nanoparticles which are based on nonscanning Moiré deflectometry and Z-scan. In the Moiré deflectometry setup, two lasers are used, one is used as pump laser which causes thermal nonlinear effects in the sample, and the second one is used as the probe laser for monitoring these effects by Moiré deflectometry system. By observing the deflected Moiré fringes, we can determine the sign of nonlinear refractive index in real time, and there would be no need for calibration or complicated calculations. The second technique for sign identification is Z-scan. In this technique, a CW 532 nm second harmonic Nd:YAG laser with a beam power of 55 mW is used as the excitation source. Results show that the nonlinear refractive index is negative for Ag nanoparticles in pure water by both methods.

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Investigating the Nonlinear Optical Response of Pepper Oil under Low Power Irradiation with Continuous Wave Visible Laser Beam

10.32792/utq/utjsci/vol7/2/29 ◽

2020 ◽

pp. 131-138

Keyword(s):

Refractive Index ◽

Nonlinear Refractive Index ◽

Nonlinear Optical ◽

Continuous Wave ◽

Diffraction Integral ◽

Visible Laser ◽

Limiting Property ◽

Kirchhoff Diffraction Integral ◽

Theoretical Results ◽

Good Agreement

The nonlinear optical properties of pepper oil are studied by diffraction ring patterns and Z-scan techniques with continuous wave beam from solid state laser at 473 nm wavelength. The nonlinear refractive index of the sample is calculated by both techniques. The sample show high nonlinear refractive index. Based on Fresnel-Kirchhoff diffraction integral, the far-field intensity distributions of ring patterns have been calculated. It is found that the experimental results are in good agreement with the theoretical results. Also the optical limiting property of pepper oil is reported. The results obtained in this study prove that the pepper oil has applications in nonlinear optical devices.

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Analisis Soal Matematika Tipe Higher Order Thinking Skills (HOTS) Tingkat SMP

Jurnal Pemikiran dan Penelitian Pendidikan Matematika (JP3M) ◽

10.36765/jp3m.v2i2.24 ◽

2020 ◽

Vol 2 (2) ◽

pp. 112-129

Author(s):

Lelly Oktafiana ◽

Iis Holisin ◽

Himmatul Mursyidah

Keyword(s):

Power Level ◽

Thinking Skills ◽

Higher Order Thinking Skills ◽

National Examination ◽

Class Viii ◽

Valid Test ◽

Grade Material ◽

Data Collection Technique ◽

High Level

This study aims to describe the quality of the 2018 Mathematics National Examination (UN) in the HOTS types at the junior high level in terms of the level of validity, reliability, problem differentiation power, level of difficulty and distractor. This type of research is a descriptive study. The research was conducted at SMP Muhammadiyah 4 Surabaya and SMP Negeri 13 Surabaya for students in class VIII. The data collection technique used is a test. The test was taken from the 2018 math UN questions in odd semester VIII grade material including HOTS type. The number of UN mathematics questions in 2018 in the odd semester VIII class material consisted of 12 questions with 25% including LOTS types and 75% including HOTS types. The results showed: (1) 100% valid test questions, (2) high question reliability, (3) good problem differentiation power, (4) the difficuly level of the question 77,77% categorized as moderate and 2 question 22,23% are categorized as difficult, (5) there are 2 questions with one of the answer options do not work.

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Solvent Effects on The Nonlinear Refractive Index of Bromocresol Purple at Three Excitation Wavelengths

Journal of Physics Conference Series ◽

10.1088/1742-6596/1818/1/012103 ◽

2021 ◽

Vol 1818 (1) ◽

pp. 012103

Author(s):

Sarah H. Halboos ◽

Ahmed. B. Sharba

Keyword(s):

Refractive Index ◽

Solvent Effects ◽

Nonlinear Refractive Index ◽

Bromocresol Purple

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Molecular Refraction and Nonlinear Refractive Index of Supercritical Carbon Dioxide under Clustering Conditions

Russian Journal of Physical Chemistry B ◽

10.1134/s1990793119070261 ◽

2019 ◽

Vol 13 (7) ◽

pp. 1214-1219 ◽

Cited By ~ 1

Author(s):

E. I. Mareev ◽

V. A. Aleshkevich ◽

F. V. Potemkin ◽

N. V. Minaev ◽

V. M. Gordienko

Keyword(s):

Carbon Dioxide ◽

Refractive Index ◽

Supercritical Carbon Dioxide ◽

Nonlinear Refractive Index ◽

Molecular Refraction ◽

Supercritical Carbon

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Metal artifacts in intraoperative O-arm CBCT scans

BMC Medical Imaging ◽

10.1186/s12880-020-00538-4 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Juha I. Peltonen ◽

Touko Kaasalainen ◽

Mika Kortesniemi

Keyword(s):

Image Quality ◽

Imaging Modality ◽

Nonlinear Effects ◽

Exposure Level ◽

Metal Artifacts ◽

Imaging Protocol ◽

Metal Implants ◽

Comprehensive Determination

Abstract Background Cone-beam computed tomography (CBCT) has become an increasingly important medical imaging modality in orthopedic operating rooms. Metal implants and related image artifacts create challenges for image quality optimization in CBCT. The purpose of this study was to develop a robust and quantitative method for the comprehensive determination of metal artifacts in novel CBCT applications. Methods The image quality of an O-arm CBCT device was assessed with an anthropomorphic pelvis phantom in the presence of metal implants. Three different kilovoltage and two different exposure settings were used to scan the phantom both with and without the presence of metal rods. Results The amount of metal artifact was related to the applied CBCT imaging protocol parameters. The size of the artifact was moderate with all imaging settings. The highest applied kilovoltage and exposure level distinctly increased artifact severity. Conclusions The developed method offers a practical and robust way to quantify metal artifacts in CBCT. Changes in imaging parameters may have nonlinear effects on image quality which are not anticipated based on physics.

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