Ultra-high Negative Dispersion Research Articles

Design and analysis of a hexagonal circular photonic crystal fibre with ultra-high negative dispersion and low confinement loss

This paper proposes a Hexagonal Circular Photonic Crystal Fiber (HC-PCF) with uniform tiny air holes around the core, obtaining ultra-high negative dispersion, high Birefringence and low confinement loss. The modal properties of the HC-PCF are investigated using the full-vectorial-Finite Element Method (FEM) with a perfectly matched layer as the boundary condition. The numerical investigations show ultra-high negative dispersion of −25503 ps/nm.km, a birefringence of 1.36×10-2, a nonlinearity of 38.34w-1km-1 and a confinement loss of 4.95×10-3 dB km-1 at the wavelength of 1550 nm. Moreover, the proposed HC-PCF exhibits a high negative dispersion and multiple Zero Dispersion within the 800 to 2000 nm wavelengths range. Specifically, the high negative dispersion, low optical Confinement Loss, and multiple Zero Dispersion Wavelengths (ZDW) give the proposed HC-PCF high Power Spectral Density (PSD). These characteristics make the proposed fibre suitable for long-range telecommunication networks and optical sensing.

Coaxial dual-core dispersion compensation photonic crystal fiber with wavelength-tunable ultrahigh negative dispersion

A coaxial dual-core wavelength-tunable dispersion compensation photonic crystal fiber (WT-DC-PCF) is designed in this paper. The tunable range of 1512–1587 nm with an ultrahigh negative dispersion of − 27315.76 p s / ( n m ⋅ k m ) at 1550 nm has been obtained simultaneously by filling the temperature-sensitive material into the air holes of the WT-DC-PCF. The full width at half-maximum is up to 12.4 nm, and a low confinement loss is always maintained. In addition, the phase-matching wavelength is basically linear with the temperature, which can be accurately adjusted to 1550 nm. Therefore, the proposed WT-DC-PCF is able to be used in achieving complete dispersion compensation in communication systems.

Ultra-high negative dispersion compensating circular–shaped PCF with highly birefringent and nonlinear characteristics for optical applications

Ultra-high negative dispersion compensating circular–shaped PCF with highly birefringent and nonlinear characteristics for optical applications

Design of a broadband dispersion compensated ultra-high nonlinear photonic crystal fiber

A photonic crystal fiber (PCF) with four circular rings of air holes expanded toward the cladding region is proposed. Four circular tiny air hole rings have been used between the air holes in a regular circular PCF to achieve low dispersion and confinement loss. Additionally, the core region is perforated with a rectangular-shaped hole filled with an extremely nonlinear material, gallium phosphide, to achieve the desired level of nonlinearity. We achieved extremely high nonlinearity and birefringence values of 4.6104 W−1 km−1 and 0.078 at the 1.55 µm telecommunication window by doing so. Further, we observed the structure with varying pitch (Ʌ) values and found a significant reduction in dispersion and confinement loss, as well as a decrease in effective material loss. Thus, at 1.55 µm, an ultra-high negative dispersion of − 8000 ps/nm km is achieved, particularly with Ʌ = 1.8 µm, along with extremely low confinement and material losses of 10–9 dB/km and 0.017 cm−1, respectively. Similarly, other critical parameters such as the power fraction, numerical aperture, and effective area have been examined. Hence, owing to these enhanced optical properties, the proposed PCF is capable of effectively compensating for dispersion, generating supercontinuum, and maintaining polarization.

Ultra-high negative dispersion compensating modified square shape photonic crystal fiber for optical broadband communication

In this work, a modified square photonic crystal fiber (MS-PCF) architecture is exposed with ultra-high negative dispersion for communication window. The validation of the model is successfully performed by applying an efficient full-vector finite element method (FV-FEM) with anisotropic perfectly matched layers (PMLs) for precise simulation of PCFs. Additionally, waveguide dispersion engineering is accomplished by tuning the structural parameters of the MS-PCF. From the numerical investigation, negative dispersion behavior permits remarkable suppression rather than positive dispersion. It offers the high negative dispersion of −2357.54 ps/nm/km and Kerr nonlinearity (γ) of 74.68 W−1 km−1 simultaneously at the operating wavelength, λ = 1550 nm. Nevertheless, the designed fiber ensures the mono mode operation in the entire band of interest from λ = 1340 nm to λ = 1580 nm. MS-PCF with these outstanding optical performances has distinguished potency to be practiced as a dispersion compensating fiber in optical communication systems.

Chirped-apodized Thue-Morse quasiperiodic structures for multichannel optical dispersion compensation

Nowadays, optical data transmission systems are significantly involved in telecommunication networks. Particularly, hundreds of data channels can be sent concurrently over a single optical fiber through dense wavelength division multiplexing (DWDM) and optical time division multiplexing technologies. Nevertheless, dispersion imposes main limitations for having high capacity systems with high transmission rates. This paper suggests a new dispersion compensating scheme by introducing one-dimensional chirped and apodized Thue-Morse quasiperiodic structures. Numerical investigations of the dispersion features of the proposed structure is presented. According to the acquired relatively smooth and negative slope group delay (GD) along with corresponding negative constant group velocity dispersion (GVD) of the reflection bands, it would be possible to apply the suggested structure in an efficient way in DWDM applications for multiband dispersion compensation in optical communication systems. The designed multilayer structure with short physical length and ultrahigh negative dispersion coefficient and with the free spectral range (FSR) of about 0.8 nm meets the International Telecommunication Union-Telecommunication Standardization (ITU-T) Sector requirements. Besides, the impact of main structural design parameters on the spectral features of the suggested system are presented in this paper.

Highly negative dispersion dual-core liquid crystal photonic crystal fiber

Abstract A novel design for dispersion compensation based on dual core liquid crystal photonic crystal fiber (DC-LCPCF) is reported and analyzed. The new structure is based on the optical coupling between the dual cores of the suggested PCF. The full vectorial finite element method (FVFEM) is used to study the dispersion characteristics of the DC-LCPCF. A very large negative chromatic dispersion of 27101.8 ps/(nm-km) is achieved at λ = 1.542 μm with circular air holes only. In addition, the proposed PCF has good tunability with the temperature. Further, the coupling can be switched between transverse electric (TE) and transverse magnetic (TM) modes through external electric field due to the infiltration of the liquid crystal (LC) material. Furthermore, the DC-LCPCF with elliptical air holes has an ultra-high negative dispersion of 289,118 ps/(nm-km) at λ = 1.543 μm.

Carbon disulphide (CS2) enriched photonic crystal fiber for nonlinear application: a FEM scheme

In this letter, a numerical investigation of the Carbon disulfide ( $$CS_2$$ ) embedded photonic crystal fiber has been reported. Numerical results incurred by using finite element method. A circular perfectly matched layer is used to simulate the design. It indicates high Kerr nonlinearity of 13,667 $$\hbox {W}^{-1}\,\hbox {km}^{-1}$$ at the operating wavelength $$\lambda$$ = 1000 nm. In addition, effective mode area, confinement factor, numerical aperture, power fraction, dispersion and V-parameter have been also studied. Geometric parameters have been also tuned to observe optical characteristics over the specified domain of operating wavelength. The model shows ultrahigh negative dispersion profile of − 254.67 ps/(nm km) at $$\lambda$$ = 1000 nm. Therefore excellent optical performances of the suggested model enables it to be used in parametric amplification, polarization maintaining nonlinear signal processing, optical nonlinear sensor, super-continuum spectrum generation, optical coherence tomography and so on.

Ultra-High Negative Dispersion Based Single Mode Highly Nonlinear Bored Core Photonic Crystal Fiber (HNL-BCPCF): Design and Numerical Analysis

In this paper, two different models of highly nonlinear bored core photonic crystal fibers (HNL-BCPCF) are presented and compared for attaining an ultra-high negative dispersion coefficient and high nonlinearity. We achieved this dispersion by tailoring a defect into the solid core of the two proposed models and appropriately scaling down the diameter of the neighboring airholes of the core. To investigate the optical transmission properties in the fiber, simulations were carried out employing the finite element method (FEM) having a perfectly matched layer. The simulation results exhibited large negative dispersion coefficients of − 2218 ps/(nm-km) and − 2221 ps/(nm-km) for the two proposed models, respectively, when the wavelength had been tuned to 1550 nm and the corresponding nonlinear coefficients stand out to be 117.6 W−1 km−1 and 118.4 W−1 km−1. The fabrication process had been made much more feasible as the design consists of circular airholes. In our analysis, this geometry of photonic crystal fiber is noticeably more robust for its successful achievement of an ultra-high negative dispersion with high nonlinearity and facilitates optical back propagation applications and dispersion compensation for optical transmission systems.

Highly nonlinear bored core hexagonal photonic crystal fiber (BC-HPCF) with ultra-high negative dispersion for fiber optic transmission system.

In this paper, we propose a bored core hexagonal photonic crystal fiber (BC-HPCF) which obtains ultra-high negative dispersion and large nonlinearity simultaneously. The aim of the proposed design is to achieve the desired optical properties by using circular air holes only to make the fiber simple and manufacturable. To investigate the light guiding properties of the proposed BC-HPCF, finite element method (FEM) with circular perfectly matched boundary layer (PML) is used. According to numerical simulation, it is possible to obtain a large value of negative dispersion of -2102 ps·nm-1·km-1 and large value of nonlinearity of 111.6 W-1 · km-1 at optimum wavelength of 1550 nm. In addition, ±2% deviation in optical characteristics is evaluated and reported in order to study the practical feasibility of the proposed BC-HPCF. The large negative dispersion and high nonlinearity of our proposed design make it a strong candidate for optical broadband communication, super continuum generation, and sensing.

Ultra-high negative dispersion and nonlinearity based single mode photonic crystal fiber: design and analysis

In this article, we have proposed a large negative dispersion coefficient and highly nonlinear polarization maintaining single mode square photonic crystal fiber. The proposed design is extremely attractive for compensation of chromatic dispersion of − 1052.60 ps/(nm km) to − 2421.90 ps/(nm km) around 1340–1640 nm wavelength band. Guiding characteristics are investigated applying finite element method containing perfectly matched layer boundary condition. Simulation outcomes ensure the possibility of large negative dispersion coefficient and low confinement loss of − 2015.30 ps/(nm km) and 3.41 × 101 dB/m respectively, at 1550 nm wavelength. The proposed fiber also exhibits highly nonlinear coefficient of 99.73 W−1 km−1 at the same wavelength. Moreover, V parameter assures the single mode operation of the structured fiber over the whole band of interest. The structural diameter variation of ± 2% over the optimum value is simulated and reported to explore the practical feasibility. Besides, effective area is also presented and explained. From overall investigations, it can be reported that the proposed fiber will be an attractive candidate in high-speed transmission system for broadband dispersion compensation, nonlinear optics and sensing applications as well.

STUDY OF THE STRUCTURE OF PHOTONIC CRYSTAL FIBER WITH HIGH NEGATIVE DISPERSION COEFFICIENT

The optical fiber communication has been second topics only to robot study for today. In the process of the Dense Wave-Length Division Multiplexing (DWDM) study, the problem of the dispersion compensate for the traditional optical fiber is a difficult problem to be solved for long distance transport information. In order to solve this problem, it is half work and times time by experimental study on photonic crystals with high negative dispersion structure. The advanced COMSOL Multiphysics many physical fields coupling calculation software is preferred. The research methods are that the structural parameters are adjusted for the traditional hexagonal photonic crystal fiber and the negative dispersion coefficient is obtained as far as possible large. Then the structure that the several layers with same spacing is designed and the structure is with ultra-high negative dispersion coefficient. The result shows that it is several ten times of the domestic level and it is 1.1 times of the international level. It is times work and half time by COMSOL Multiphysics many physical fields coupling calculation software in Modeling, mesh subdivision, calculation and analysis. The result is the theory basis for DWDM.

温度可控极高负色散光子晶体光纤的研究

温度可控极高负色散光子晶体光纤的研究

Design and Analysis of Single-Mode PCF in Optical Communication Covering E to L Bands with Ultra-High Negative Dispersion

Design and Analysis of Single-Mode PCF in Optical Communication Covering E to L Bands with Ultra-High Negative Dispersion

Proposed Square Lattice Photonic Crystal Fiber for Extremely High Nonlinearity, Birefringence and Ultra-High Negative Dispersion Compensation

Abstract A photonic crystal fiber in square lattice architecture is numerically investigated and proposed for broadband dispersion compensation in optical transmission system. Simulation results reveal that it is possible to obtain an ultra-high negative dispersion of about −571.7 to −1889.7 (ps/nm.km) in the wavelength range of 1340 nm to 1640 nm. Experimentally it is demonstrated that the design fiber covers a high birefringence of order 4.74×10‒3 at the wavelength of 1550 nm. Here, numerical investigation of guiding properties and geometrical properties of the proposed PCF are conducted using the finite element method (FEM) with perfectly match layers. Moreover, it is established more firmly that the proposed fiber successfully compensates the chromatic dispersion of standard single mode in entire band of interest. Our result is attractive due to successfully achieve ultra-high negative dispersion that is more promisor than the prior best results.

Solutions for Modal Squeeze in Dual-Concentric Core Photonic Crystal Fibers

Dual-concentric core photonic crystal fibers (DCC-PCF) were a kind of dispersion compensating fiber with ultrahigh negative dispersion. However, they usually have an undesirable characteristic, called “modal squeeze” in this letter, which causes difficulty in achieving a single-mode operation. This letter discusses a phenomenon of modal squeeze, and proposes a solution to avoid it. Finally, we give designing examples of DCC-PCFs for avoiding the modal squeeze and operating in single mode.

Ultra-high negative dispersion compensating square lattice based single mode photonic crystal fiber with high nonlinearity

This paper presents dispersion tailoring of photonic crystal fibers creating artificial defect along one of the regular square axes. A finite element method (FEM) has been enforced for numerical investigation of several guiding properties of the PCF covering a broad wavelength range about 1340–1640 nm over the telecommunication windows. According to simulation, the proposed PCF has obtained a strictly single-mode fiber, which has an ultra-high negative dispersion of about −584.60 to −2337.60 ps/(nm-km) and also possible to cover the highest nonlinearity order of 131.91 W−1 km−1 under the operating wavelength. Moreover, the proposed PCF structure experimentally focuses on higher nonlinear coefficient, which successfully compensates the chromatic dispersion of standard single mode in entire band of interest and greatly applicable to the optical transmission system. Additionally, the single mode behavior of S-PCF is explicated by employing V parameter. In our dispersion sensitive analysis, this fiber is significantly more robust due to successfully achieve ultra-high negative dispersion, which gains more promiscuous compared to the prior best results.

Tellurite based circular photonic crystal fiber with high nonlinearity and low confinement loss

Photonic Crystal Fibers (PCFs) generate great interest in the field of optical fiber technology because of its ability to tailor different optical characteristics such as birefringence, dispersion, mode area, nonlinearity etc. High index non silica based glass fibers have high nonlinearity and low loss in mid-infrared wavelength transmission. Out of this, tellurite glass is a highly suitable fiber material for infrared nonlinear applications because of its high nonlinear coefficient compared to other non-silica glasses. Typically in Photonic Crystal Fibers, air holes are arranged in hexagonal or octagonal structure.In the present investigation, a circular lattice PCF is designed with tellurite core and various optical properties such as confinement loss, effective mode area, dispersion and nonlinear coefficient are analyzed using COMSOL MultiPhysics. The proposed fiber gives very high nonlinearity with a maximum of 12,100W−1km−1 at 0.45μm, ultra high negative dispersion and very low confinement loss for a wide range of wavelengths. High nonlinearity is suitable for super continuum generation. This fiber can also be used as a dispersion compensation fiber.

A Polarization Maintaining Single-Mode Photonic Crystal Fiber for Residual Dispersion Compensation

A single-mode octagonal photonic crystal fiber (OPCF) is proposed to simultaneously achieve high birefringence and ultra-flattened ultra-high negative dispersion. Simulation results demonstrate that by introducing an elliptical air hole in the center of the core, it is possible to obtain a large average dispersion of −608.93 ps/nm/km with an absolute dispersion variation of −12.7 ps/nm/km over 1.46–1.625 $\mu \text{m}$ wavelength bands for fundamental slow-axis mode. Besides, with optimal design parameters, a high birefringence of $1.81\times 10^{\mathrm {-2}}$ and a very low confinement loss of 0.04 dB/km are achieved at 1.55 $\mu \text{m}$ . The proposed OPCF can be used in cost-effective residual dispersion compensation and optical sensors.

Analysis and optimization of a dual-core dispersion compensation fiber based on a 12-fold photonic quasicrystal structure.

In this paper, a dual-concentric-core photonic quasicrystal fiber (DCC-PQF) with a 12-fold symmetric structure has been designed to compensate for dispersion effects. To this end, a new design based on modifying the positions of the nearest air holes to the central core has been proposed for dispersion compensation, in which ultra-high negative dispersion of about -44,000 ps/(nm·km) at 1.55μm can be estimated. In addition, by optimizing structural parameters, high negative dispersion for the proposed DCC-PQF has been predicted, approximately -12,000 ps/(nm·km) at around 1.55μm, with an FWHM about 42nm in the wavelength ranges between 1529 and 1571nm, which entirely covers the C telecommunication band. Furthermore, a dispersion relation dependency on hole-to-hole spacing, first ring air hole diameters, as well as diameter of the air holes in the outer core and its position, has been investigated and discussed in detail.