NONLINEAR EFFECTS IN ERBIUM-DOPED FIBRES

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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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 refractive index in erbium-doped optical amplifiers

Optical and Quantum Electronics ◽

10.1007/bf00558479 ◽

1995 ◽

Vol 27 (10) ◽

pp. 871-880 ◽

Cited By ~ 4

Author(s):

M. Montagna ◽

S. Selleri ◽

M. Zoboli

Keyword(s):

Refractive Index ◽

Nonlinear Refractive Index ◽

Optical Amplifiers ◽

Erbium Doped

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Optical Nonlinearity of Sputtered Co3O4-SiO2-TiO2 Thin Films

MRS Proceedings ◽

10.1557/proc-703-v13.20 ◽

2001 ◽

Vol 703 ◽

Author(s):

Hiroki Yamamoto ◽

Takashi Naito ◽

Kazuyuki Hirao

Keyword(s):

Thin Films ◽

Refractive Index ◽

Excited State ◽

Absorption Coefficient ◽

Extinction Coefficient ◽

Ground State ◽

Optical Nonlinearity ◽

Tio2 Thin Films ◽

Change Mechanism ◽

Band Filling

ABSTRACTOptical non-linearity of cobalt oxide with SiO2-TiO2 additives was investigated, and the change mechanism of the refractive index (n) and extinction coefficient (k), based on the relation between band structure and optical non-linearity of the thin films, was discussed. Refractive index and extinction coefficient of Co3O4 thin films in the ground state were 3.17 and 0.42, respectively. Both n and k decreased by irradiation from a pulse laser with 650 nm of wavelength (1.91eV). These values in the excited state were 2.91 and 0.41, respectively. n2 estimated from the change of n and k was −2.8 ×10−11 m2/W. The film had a band gap corresponding to 2.06eV, indicating that it was widened by the band filling effect during the laser irradiation at 1.91eV, and this led to the decrease in absorption coefficient and refractive index.

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Erbium Doped Tellurite Glasses

MRS Proceedings ◽

10.1557/proc-244-209 ◽

1991 ◽

Vol 244 ◽

Author(s):

Jau-Sheng Wang ◽

Elias Snitzer ◽

George H. Sigel

Keyword(s):

Excited State ◽

Cross Section ◽

Cross Sections ◽

Ground State ◽

Optical Transition ◽

Emission Cross Section ◽

Excited State Absorption ◽

Tellurite Glasses ◽

Ground State Absorption ◽

Erbium Doped

ABSTRACTThe results to be presented focus on the optimization of tellurite glass compositions which are suitable both for doping with erbium oxide as well as subsequent for fiber drawing. The laser related properties, such as fluorescence spectrum, lifetime, and optical transition cross sections will be presented. Judd-Ofelt parameters for erbium in the glasses have been exploited to predict fluorescence lifetime, excited state absorption(ESA), ground state absorption(GSA) and ground state fluorescence(GSF). For comparison, the absorption cross section, emission cross section, excited state absorption(ESA)/ground state absorption(GSA)(0.8μm pumping) and fluorescence terminating in the ground state(GSF)/excited state absorption(ESA) ratios are calculated for both Al2O3-SiO2 and tellurite glasses.

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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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Study on All Optical Switching Effect of Excited State Proton Transfer Organic Molecule 3-Hydroxyflavone

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.482-484.830 ◽

2012 ◽

Vol 482-484 ◽

pp. 830-834

Author(s):

Yang Xue Guo ◽

Xiang Hong Kong ◽

Wei Yang ◽

Jia Jin Zheng

Keyword(s):

Refractive Index ◽

Excited State ◽

Proton Transfer ◽

Laser Beam ◽

Nonlinear Refractive Index ◽

Optical Switching ◽

Switching Effect ◽

All Optical ◽

Excited State Proton Transfer ◽

All Optical Switching

Abstract: We report the dependence of the all optical switching effect of 3-hydroxyflavone (3-HF) on the efficiency of excited state proton transfer (ESPT) using pump probe method. A cw probe laser beam of 632.8nm passing through the sample is switched off by a 35ps pulse pump laser beam of 355nm. We also measured the nonlinear refractive index of 3-HF in different solvents by using z-scan technique. The results show that the optical switching effect will be more obvious when the efficiency of excited state proton transfer is improved, while not proportional to the nonlinear refractive index of 3-HF.

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Nonlinear absorption coefficient and refractive index changes of two-dimensional two-electron quantum dot in rigid confinement

International Journal of Modern Physics B ◽

10.1142/s0217979219500784 ◽

2019 ◽

Vol 33 (09) ◽

pp. 1950078

Author(s):

Menberu Mengesha Woldemariam

Keyword(s):

Refractive Index ◽

Excited State ◽

Quantum Dot ◽

Absorption Coefficient ◽

Ground State ◽

State Energy ◽

Two Dimensional ◽

First Excited State ◽

Trial Wavefunction ◽

Index Changes

The Hamiltonian and wavefunctions describing two-dimensional (2D) two-electron ZnO quantum dot in rigid confinement are developed. Then the Schrödinger equation is solved analytically and numerically for determining the ground and excited state energies. The ground state energy of 2D two-electron ZnO quantum dot (QD) in rigid confinement is studied using perturbation and variational methods. The obtained result show that our trial wavefunction is good enough to describe the 2D two-electron QD in rigid confinement. The wavefunction describing the ground state is the combination of symmetric spatial wavefunction and antisymmetric spin wavefunction which is a para-state. The ground state energy eigenvalue obtained by variational technique is a little above that of a perturbation technique. Based on this; the trial wavefunction for the excited state is developed. The excited state energy of 2D two-electron ZnO QD in rigid confinement is studied computationally using variational method. The wavefunction describing the excited state is the combination of symmetric spatial wavefunction with antisymmetric spin wavefunction (para-state) or vice versa (ortho-state). The para and ortho-state energies of the first excited state are calculated and their difference is twice of the exchange energy. Based on the obtained energy eigenvalues of the ground and the first excited state at the value of the coupling constant [Formula: see text] [Formula: see text] 1, the third-order nonlinear absorption coefficient and refractive index changes are investigated. The optical transition is only considered between the two lowest para states.

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