Search

This work focuses on the study of the paraxial wave model with a space–time fractional form. This model has more importance for describing light propagation in nonlinear optical fibers and telecommunication lines. The main aim of this work is to observe the effect of the fractional parameters and compare the truncated M -fraction with the beta-fraction, conformable fraction form, and classical form of the PW model. For this observation, we applied the Simplest equation technique to acquire analytical solutions to the space–time (spatiotemporal) M -fractional paraxial wave model. We are able to acquire several new optical soliton solutions, including periodic waves, kink-type waves, rogue-type waves, and several novel periodic waves, by providing the appropriate fractional parametric values. These solutions have significance for shedding light on a number of physical phenomena in the realms of optical fiber and communication sciences. The diverse values of fractional parameters and the three-dimensional and contour plot graphs of certain chosen solutions are depicted, which are the most accurate physical characterizations of the outcomes. We also sketch the comparative graph of diverse fractional forms and the classical form of the paraxial wave equation in two-dimensional plots. Consequently, our findings represent an important breakthrough in this complex area and help further develop our comprehension of the behavior of solitons. [ABSTRACT FROM AUTHOR]

In this work, we realised the soliton solutions of nonlinear Schrödinger equation (NLSE) that arise from optical fibers, we considered the modified Sardar sub-equation method (MSSEM) to find solitary solutions analytically. The stability of the retrieved soliton solutions realised from the NLSE are investigated. We demonstrate the soliton solutions that are stable and can last for a very long time without losing its form or energy under specific circumstances and those soliton solutions that are unstable. The MSSEM is a frequently employed technique in research for addressing specific mathematical modeling or physical phenomena problems. Its selection in this specific study might stem from its proven efficacy in handling the particular problem under investigation. The decision to utilize MSSEM could be driven by several considerations, including its precision, computationally efficient, effectiveness, greater accuracy and capability to manage intricate systems. Finally, our method offers greater flexibility in modeling various physical phenomena, which makes it particularly useful in applications in diverse fields such as quantum mechanics and nonlinear optics. The findings have ramifications for the architecture of optical fiber communications and offer significant new insights into the behavior of solitons in optical systems. The NLSE has proven to be an effective tool for understanding wave behavior in fiber optics. Its applications have helped engineers and scientists optimize the design of optical fibers and predict the behavior of various conditions. Moreover, our study provides insights into the fundamental properties of solitary solutions in the NLSEs and their practical implications in physical systems. [ABSTRACT FROM AUTHOR]

This study explores the impact of the integrability criterion on nonlinear Schrödinger (NLS ) equations with mixed derivatives, specifically focusing on the Rangwala–Rao ( R R ) equation formulated by A. Rangwala in 1990. The objective of this investigation is to enhance our understanding of the dispersion effect by examining novel soliton wave solutions and their interactions. By doing so, we aim to gain insights into the behavior of the slowly changing envelope of the electric field and pulse propagation in optical fibers. To achieve this, we employ recent computational approaches, including the Sardar Sub-equation and modified rational methods, to identify distinctive solitary wave solutions for the analyzed model. The significance of studying the Rangwala–Rao equation lies in its potential contribution to the development of more efficient optical fiber communication systems. The presented numerical solutions in this paper showcase the dynamic nature of optical fiber pulse propagation, thereby highlighting the originality of this work compared to existing scholarly contributions. [ABSTRACT FROM AUTHOR]

In the development of orbital angular momentum (OAM) mode division multiplexing, the capacity of optical fiber communication must be improved. However, owing to dispersion and confinement loss, many OAM modes do not propagate stably over a long distance in optical fibers. In this work, the effects of the size, number, shape, number of layers, and layer spacing of air holes in the cladding of the fiber on the dispersion and confinement loss are analyzed based on a simple structure. The trends are studied and summarized to facilitate the design of optical fibers to achieve stable transmission of OAM modes over a long distance. [ABSTRACT FROM AUTHOR]

The performance enhancement using multimodulus blind equalization algorithm for compensating in-phase/ quadrature-phase (I/Q) mismatch in orthogonal frequency division multiplexing optical communication system is investigated. The mathematical theory of I/Q imbalance is analyzed. Then, a compensation scheme with two-tap equalizer is implemented, with this scheme, the joint compensation of transmitter and receiver with optical channel that contains noise attenuation and chromatic dispersion is realized. Simulation shows that the performance degradation caused by I/Q imbalance can be compensated by the scheme with multimodulus blind equalization algorithm effectively regardless of the modulation order and channel distortion. [ABSTRACT FROM AUTHOR]

A $$\hbox {LP}_{11}$$ mode filtering method based on two-mode fiber Bragg grating is proposed in this paper and its feasibility is verified experimentally. The experimental results illustrate that $$\hbox {LP}_{11}$$ mode can be obtained in the transmission light of the two-mode FBG when the laser operates at 1,064.7 nm; moreover, by using a three ports circulator, the $$\hbox {LP}_{11}$$ mode can also be obtained in the reflection light of the two-mode FBG at 1,062.8 nm. Furthermore, by adjusting core-offset splicing distance between the laser's pigtail and the two-mode fiber, the insertion loss of the $$\hbox {LP}_{11}$$ mode is optimized. And in the case of splicing at the optimal core-offset distance, at 1,064.7 nm, the insertion loss of the $$\hbox {LP}_{11}$$ mode obtained at the transmission end is 5.98 dB, and at 1,062.8 nm, the insertion loss of the $$\hbox {LP}_{11}$$ mode obtained at the reflection end is 9.30 dB. Due to all-fiber structure, this method of filtering $$\hbox {LP}_{11}$$ mode by utilizing the two-mode FBG is easy to implement, and the two-mode FBG is easy to couple with the fiber link. [ABSTRACT FROM AUTHOR]

Unique dispersion characteristics and enhanced nonlinearity make the small-core photonic crystal fiber (PCF) an ideal candidate for nonlinear optical devices to telecommunication applications. Some technical reasons behind great research interest of highly nonlinear PCFs in optical communication components are reviewed. Nonlinear effects in highly nonlinear PCFs and their research progress are presented. Several typical applications including WDM sources, optical amplification, optical switching, wavelength conversion, optical regeneration and all-optical demultiplexing etc are introduced, together with state-of-the art performances. Some new possible applications and future prospects are discussed. [ABSTRACT FROM AUTHOR]

We investigate the transmission performance of N × 40 Gbps carrier-suppressed return-to-zero (CS-RZ) and duobinary CS-RZ (DCS-RZ) modulated wavelength division multiplexed (WDM) signals over the standard single-mode fiber (SSMF) based on non-ideal Mach-Zehnder (MZ) modulators through numerical simulations. In addition to that, the impact on receiver margin related to the residual chirp due to an asymmetry ratio of modulators as well as the effect of the applied chirp of modulators has been studied. As the asymmetry ratio of modulators is increased, dispersion penalties are increased asymmetrically at around the zero dispersion wavelength for the CS-RZ format. The DCS-RZ modulation format has a symmetric behavior due to different characteristics of the residual chirp of modulators. The receiver margin for the DCS-RZ modulation format is larger than the CS-RZ modulation format above the asymmetry ratio of 0.82 of modulators (extinction ratio of 20 dB) with the optimal ΔλDCF. By controlling the negative/positive applied chirp of the first/second modulator, dispersion penalties can be reduced for both the CS-RZ and DCS-RZ formats. In the DCS-RZ format compared to the CS-RZ format, the effect of the applied chirp of the first modulator is more dominant than that of the second modulator. The simulation results show that the receiver margin is limited by the asymmetry ratio of modulators as well as a deviated wavelength from the zero dispersion wavelength of dispersion compensating fibers (DCF) in order to be fully post-compensated. Dispersion penalties can be reduced with appropriate chirp parameters of two non-ideal modulators. [ABSTRACT FROM AUTHOR]

For combining different single photon channels into a single path, we use an effective and reliable technique which is known as quantum multiple access. We take advantage of an add-drop multiplexer capable of pushing and withdrawing a single photon into an optical fiber cable which carries quantum bits from multiusers. In addition to this, spreading spreads the channel noise at receiver side and use of filters stop the overlapping of adjacent channels, which helps in reducing the noise level and improved signal-to-noise ratio. In this way, we obtain enhanced performance of code division multiple access-based QKD links with a single photon without necessity of amplifiers and modulators. [ABSTRACT FROM AUTHOR]

We propose a method to fabricate chiral long-period grating (CLPG) by rotating the standard single mode fiber which is fixed on two fiber holders but with an axis-offset. We show that, compared with traditional fabrication methods, this axis-offset method is capable of obtaining identical resonance wavelengths of the CLPGs for the same grating period. We investigate the performance of CLPGs by detecting the interference between the light emerging from CLPGs and a reference light. The achieved forklike and spiral interference patterns both confirm the generation of ± 1-order optical vortex through CLPG. Experimental results indicate that high-quality CLPGs can be easily and repeatedly fabricated by this method. [ABSTRACT FROM AUTHOR]