SOLITON PROPAGATION IN SATURABLE NONLINEAR FIBRE COUPLERS — VARIATIONAL AND NUMERICAL RESULTS

The problem of optical soliton propagation in couplers with saturation of nonlinear refractive index is investigated using a simple variational approach. From this study, important features relating to optical switching and soliton eigen-states are revealed. For instance, a parameter, γ max , which characterizes the limiting effect of saturation in optical switching, is identified. We carry out numerical solutions to the problem and confirm that the approximate approach does give results agreeing with those from the simulation.

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Fused ring effect on optical nonlinearity and structure property relationship of anthracenyl chalcone based push-pull chromophores

PLoS ONE ◽

10.1371/journal.pone.0257808 ◽

2021 ◽

Vol 16 (9) ◽

pp. e0257808

Author(s):

Dian Alwani Zainuri ◽

Mundzir Abdullah ◽

Muhamad Fikri Zaini ◽

Hazri Bakhtiar ◽

Suhana Arshad ◽

...

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Electrostatic Potential ◽

Nonlinear Refractive Index ◽

Optical Switching ◽

Nonlinear Optical ◽

Continuous Wave ◽

Excited State Absorption ◽

Nonlinear Optical Properties ◽

Closed Aperture

The Ultraviolet-visible (UV-Vis) spectra indicate that anthracenyl chalcones (ACs) have high maximum wavelengths and good transparency windows for optical applications and are suitable for optoelectronic applications owing to their HOMO–LUMO energy gaps (2.93 and 2.76 eV). Different donor substituents on the AC affect their dipole moments and nonlinear optical (NLO) responses. The positive, negative, and neutral electrostatic potential regions of the molecules were identified using molecular electrostatic potential (MEP). The stability of the molecule on account of hyperconjugative interactions and accompanying charge delocalization was analyzed using natural bond orbital (NBO) analysis. Open and closed aperture Z-scans were performed using a continuous-wave frequency-doubled diode-pumped solid-state (DPSS) laser to measure the nonlinear absorption and nonlinear refractive index coefficients, respectively. The valley-to-peak profile of AC indicated a negative nonlinear refractive index coefficient. The obtained single crystals possess reverse saturation absorption due to excited-state absorption. The structural and nonlinear optical properties of the molecules have been discussed, along with the role of anthracene substitution for enhancing the nonlinear optical properties. The calculated third-order susceptibility value was 1.10 x10-4 esu at an intensity of 4.1 kW/cm2, higher than the reported values for related chalcone derivatives. The NLO response for both ACs offers excellent potential in optical switching and limiting applications.

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Optical soliton perturbation and conservation law with Kudryashov’s refractive index having quadrupled power-law and dual form of generalized nonlocal nonlinearity

Semiconductor Physics Quantum Electronics & Optoelectronics ◽

10.15407/spqeo24.01.064 ◽

2021 ◽

Vol 24 (1) ◽

pp. 64-70

Author(s):

Y. Yildirim ◽

◽

A. Biswas ◽

A.H. Kara ◽

M. Ekici ◽

...

Keyword(s):

Refractive Index ◽

Power Law ◽

Nonlinear Refractive Index ◽

Conservation Law ◽

Optical Solitons ◽

Optical Soliton ◽

Complete Picture ◽

Nonlocal Nonlinearity ◽

Dual Form ◽

Soliton Perturbation

This paper is devoted to optical solitons for Kudryashov’s law of nonlinear refractive index, which stem from quadrupled-power law and dual form of nonlocal nonlinearity. The conservation law has been also exhibited to paint a complete picture of the model.

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Cubic–Quartic Solitons in Couplers with Optical Metamaterials Having Power Law of Refractive Index

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218863520500095 ◽

2021 ◽

pp. 2050009

Author(s):

Elsayed M. E. Zayed ◽

Mohamed E. M. Alngar ◽

Reham M. A. Shohib ◽

Anjan Biswas ◽

Mehmet Ekici ◽

...

Keyword(s):

Refractive Index ◽

Power Law ◽

Nonlinear Refractive Index ◽

Soliton Solutions ◽

Optical Soliton ◽

Optical Metamaterials

This paper studies couplers in optical metamaterials that come with power law of nonlinear refractive index. The Kudryashov’s approach reveals bright, singular as well as bright-singular straddled optical soliton solutions. Both twin-core couplers and multiple-core couplers are studied.

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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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Pure-Cubic Optical Soliton Perturbation with Complex Ginzburg–Landau Equation Having a Dozen Nonlinear Refractive Index Structures

Journal of Communications Technology and Electronics ◽

10.1134/s1064226921050120 ◽

2021 ◽

Vol 66 (5) ◽

pp. 481-544

Author(s):

Elsayed M. E. Zayed ◽

Mohamed E. M. Alngar ◽

Anjan Biswas ◽

Mehmet Ekici ◽

Salam Khan ◽

...

Keyword(s):

Refractive Index ◽

Nonlinear Refractive Index ◽

Landau Equation ◽

Optical Soliton ◽

Index Structures ◽

Ginzburg Landau ◽

Soliton Perturbation ◽

Ginzburg Landau Equation

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TYPE-II SUPERLATTICES AND VARIABLE OVERLAP SUPERLATTICES IN TOTAL INTERNAL REFLECTION SWITCHES FOR THE LONGWAVE INFRARED

Journal of Nonlinear Optical Physics & Materials ◽

10.1142/s0218199193000255 ◽

1993 ◽

Vol 02 (03) ◽

pp. 415-436 ◽

Cited By ~ 1

Author(s):

E.R. YOUNGDALE ◽

J.R. MEYER ◽

C.A. HOFFMAN ◽

F.J. BARTOLI ◽

W.I. WANG

Keyword(s):

Refractive Index ◽

Nonlinear Refractive Index ◽

Total Internal Reflection ◽

Optical Switching ◽

Refractive Index Change ◽

Realistic Model ◽

Internal Reflection ◽

Type Ii ◽

Index Change ◽

Type Ii Superlattices

We derive explicit criteria for the properties required of a semiconductor nonlinear medium suitable for use in all-optical switching devices employing total internal reflection. Transmission as a function of laser intensity and film thickness has been calculated using a realistic model for penetration of the evanescent beam under TIR conditions. Requirements based on these results include a large nonlinear refractive index, large index change at saturation and small absorption coefficient. We show that unlike previously-studied semimetals and narrow-gap semiconductors, Type-II superlattices such as InAs-GaSb and variable-overlap superlattices (variants of Type-II which include a spacer between the layer containing the conduction-band minimum and that containing the valence band maximum) such as InAs-AlSb-GaSb hold prospects for satisfying all of these requirements simultaneously. As the free carrier lifetime will have a crucial influence on device performance, we have initiated a systematic experimental study of electron-hole recombination in InAs-based superlattices. From degenerate and nondegenerate four-wave mixing experiments, we have also determined nonlinear optical coefficients as a function of difference frequency and intensity. An InAs-GaSb superlattice has been found to display a refractive index change of ≈ 0.1, as well as device figures of merit which slightly surpasses any previously reported for weakly-saturating nonlinearities at CO 2 wavelengths. It is anticipated that future experiments on Type-II superlattices with longer lifetimes may yield nearly two orders of magnitude additional improvement in the nonlinear refractive index.

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