Optical Demultiplexer Research Articles

Endless optical domain polarization demultiplexing in 2000 km simplified coherent transceiver for long-distance transmission

We demonstrate an endless optical domain polarization demultiplexing scheme that was realized in a 96 Gbaud-PS-16QAM coherent transmission system to alleviate the data processing pressure of the DSP in the receiver. It can be effectively employed in the 140 km fiber link (Metro DCI) and extended to the 2000 km optical fiber networks (Long haul DCI or backbone networks transmission). It can track 10 krad/s state of polarization (SOP) changes following Rayleigh distribution which is the general statistical case for real fibers. The proposed method has a noise tolerance equivalent to that induced by a 2000 km transmission, with OSNR as low as 20 dB, with a maximum PMD of 4 ps and a mean DGD of 2.5 ps.

Design and simulation of an enhanced optical demultiplexer using photonic crystal resonators

The purpose of this paper is to examine the design, simulation, and optimization of a demultiplexer optical system using photonic crystal resonators. Utilizing the distinct properties of photonic crystals, the proposed device achieves high-quality resonances, efficient wavelength separation, and minimal crosstalk. These characteristics are crucial for enhancing the performance of dense wavelength division multiplexing (DWDM) systems, which require precise and efficient channel separation to manage increasing data traffic. Extensive simulations conducted with the RSoft CAD tool explore the impact of varying resonator parameters such as refractive index, geometric dimensions, and material composition on the device's performance. The results indicate substantial improvements in transmission efficiency and quality factor, with average values of 98.675% and 3131.125, respectively. Furthermore, the ability to fine-tune these parameters allows for the customization of the demultiplexer to specific wavelength ranges, making it highly adaptable for various telecommunications applications. This research aims to propel the development of compact, high-performance photonic devices that meet the growing demands of modern communication networks, ultimately contributing to more efficient and reliable optical communication systems.

Design and Simulation of a Three-Channel Plasmonic Demultiplexer in an MIM Waveguide

This study proposes a structure for optical plasmonic demultiplexers based on nanodisk/nanoring resonators in metal-insulator-metal (MIM) plasmonic waveguides. The proposed structure can transmit the desired wavelength spectra, including telecommunication and visible waves. It consists of a bus waveguide, several nanodisks and nanorings, and three drop waveguides, consisting of several filters that can be extended to N×1 channels. The FWHM of the designed structure was calculated to be approximately 18 nm. The transmission spectrum of each demultiplexer channel can be easily adjusted by changing the geometric parameters and refractive index. As the waveguide refractive index increases, the transmission spectrum shifts to higher wavelengths, and its amplitude decreases due to internal structural losses. Therefore, the differences between the waveguide and metal refractive indices gradually decrease, and the light confinement decreases in the waveguide, leading to an increase in FWHM. The outputs of each channel have two sharp resonance modes, resulting from the coupling of two interacting cavities (ring and disk) due to the Fano resonance phenomenon. This study employed a two-dimensional (2D) finite difference time domain (FDTD) numerical method and simulation by FDTD Lumerical software to evaluate the transmission properties.

Design and analysis of high performance 1×N optical wavelength demultiplexers based on MIM waveguide with polygon resonators

Confinement of the light at the subwavelength scale makes photonic devices more efficient in applications such as optical filtering, switching, and sensing with their low dimensions. Metal-insulator- metal waveguide-based configurations present many paths for manipulating light at the wide range of the electromagnetic spectrum. For that purpose, in this study, a wavelength demultiplexer (WDM) based on a metal-insulator-metal (MIM) waveguide is numerically investigated by finite difference time domain (FDTD) method. Proposed WDMs have cascade polygon resonators. After optimizing the fundamental filter, this structure is formed as 1×N demultiplexers. The proposed demultiplexers have two- and three channels. The minimum full width at half-maximum (FWHM) value for these channels is 20.02 nm and the maximum quality factor value is 47.7 at 954.9 nm wavelength. The minimum crosstalk value is obtained as -30.37 dB for this study. The proposed 1×N demultiplexers have potential tools to design low-cost integrated optical circuits for specific wavelengths.

Optical demultiplexers based on graphene ring resonators

Optical demultiplexers based on graphene ring resonators

Silicon-Nanowire-Based 100-GHz-Spaced 16λ DWDM, 800-GHz-Spaced 8λ LR-8, and 20-nm-Spaced 4λ CWDM Optical Demultiplexers for High-Density Interconnects in Datacenters

Several types of silicon-nanowire-based optical demultiplexers (DeMUXs) for use in short-reach targeted datacenter applications were proposed and their spectral responses were experimentally verified. First, a novel 100-GHz-spaced 16λ polarization-diversified optical DeMUX consisting of 2λ delayed interferometer (DI) type interleaver and 8λ arrayed waveguide gratings will be discussed in the spectral regimes of C-band, together with experimental characterizations showing static and dynamic spectral properties. Second, a novel 800-GHz-spaced 8λ optical DeMUX was targeted for use in LR (long reach) 400 Gbps Ethernet applications. Based on multiple cascade-connected DIs, by integrating the extra band elimination cutting area, discontinuous filtering response was analytically identified with a flat-topped spectral window and a low spectral noise of <−20 dB within an entire LR-8 operating wavelength range. Finally, a 20-nm-spaced 4λ coarse wavelength division multiplexing (CWDM)-targeted optical DeMUX based on polarization diversity was experimentally verified. The measurement results showed a low excessive loss of 1.0 dB and a polarization-dependent loss of 1.0 dB, prominently reducing spectral noises from neighboring channels by less than −15 dB. Moreover, TM-mode elimination filters were theoretically analyzed and experimentally confirmed to minimize unwanted TM-mode-oriented polarization noises that were generated from the polarization-handling device. The TM-mode elimination filters functioned to reduce polarization noises to much lower than −20 dB across the entire CWDM operating window.

All‐optical Tera Hertz Optical Asymmetric Demultiplexer‐based Memory at a data rate of 300 Gbps

AbstractAll‐optical memory units play an important role in the operation of an optical computer. In these communications, we have designed all‐optical single‐bit memory unit or latch using Tera Hertz Optical Asymmetric Demultiplexer. The performance of single‐bit memory unit is evaluated and numerically simulated by MATLAB. We have numerically calculated the output extinction ratio (35.57 dB), contrast ratio (36.61 dB), and Q value (40.34) to analyze the memory or latch circuit. High values of extinction ratio, contrast ratio, and Q confirm the feasibility of the single‐bit memory unit.

WDM C-band four channel demultiplexer using cascaded multimode interference on SiN strip waveguide structure

Back reflection challenges significantly constrain the efficiency of optical communication networks employing dense wavelength division multiplexing (DWDM) technology, particularly those based on Silicon (Si) Multimode Interference (MMI) waveguides. To mitigate this limitation, we present a novel 1×4 optical demultiplexer design using MMI within a Silicon-Nitride (SiN) strip waveguide configuration, operating within the C-band spectrum. Our design was optimized using AI-enhanced RSoft-CAD simulations that combined the Beam Propagation Method (BPM) and Finite-Difference Time-Domain (FDTD) techniques, integrated with convolutional neural network (CNN) machine learning algorithms. The simulation results demonstrate that the proposed device efficiently transmits four channels with 10 nm spacing in the C-band, showing low power loss ranging from 1.98-2.35 dB, a broad bandwidth of 7.68-8.08 nm, and excellent crosstalk suppression between 20.8-23.4 dB. Leveraging the low refractive index of SiN, we achieve ultra-low back reflection of 40.58 dB without requiring specialized angled MMI designs, which are often necessary in Si-based MMI technology. Consequently, this SiN-based MMI demultiplexer provides an effective solution for DWDM systems, enabling high data transmission rates with minimal back reflection in optical communication networks.

PERFORMANCE ANALYSIS OF OPTICAL PARALLEL FULL ADDER USING ARTIFICIAL NEURAL NETWORK

A verbal exchange today wishes for quick operational progress. This can be accomplished by replacing devices that are primarily concerned with commutation and logic with photon-based systems instead of the usual data service, the electron. The basic building blocks of superior frames are called gates. With the aid of these gates, various logical and mathematical operations can be performed. All-optical arithmetical and logical processes are eagerly expected in high-speed dialogue frameworks. In this chapter, we’ve introduced parallel models for adding two binary digits that are based on Sagnac gates with help from semiconductor optical amplifiers (SOA) and terahertz optical asymmetric demultiplexers (TOAD). We created a Full adder that works in parallel using only two TOADs as total switches. Using artificial neural networks (ANN), we have created a model of this circuit that is equivalent. Utilizing ANN, this circuit design has been validated. This optical circuit is now capable of synthesizing light as an input and successfully structuring the aspiration output in addition to speeding up calculation. This parallel circuit’s biggest advantage is that it doesn’t need synchronization for distinct inputs. An ANN model was used to analyze this circuit’s performance in detail.

Silicon-Nanowire-Type Polarization-Diversified CWDM Demultiplexer for Low Polarization Crosstalk.

Coarse wavelength division multiplexing (CWDM)-targeted novel silicon (Si)-nanowire-type polarization-diversified optical demultiplexers were numerically analyzed and experimentally verified. The optical demultiplexer comprised a hybrid mode conversion-type polarization splitter rotator (PSR) and a delayed Mach-Zehnder interferometric demultiplexer. Si-nanowire-based devices were fabricated using a commercially available Si photonics foundry process, exhibiting nearly identical spectral responses regardless of the polarization states of the input signals under the PSR. The experiment demonstrated a low insertion loss of 1.0 dB and a polarization-dependent loss of 1.0 dB, effectively suppressing spectral crosstalk from other channels by less than -15 dB. Furthermore, a TM-mode rejection-filter-integrated optical demultiplexer was designed and experimentally validated to mitigate unwanted TM-mode-related polarization crosstalk that arose from the PSR. It exhibited an improved polarization crosstalk rejection efficiency of -25 dB to -50 dB within the whole CWDM spectral range.

Optical label-based cost-effective DWDM optical network performance monitoring using low-bandwidth PD with novel SRS mitigation DSP

Large-scale dense wavelength division multiplexing (DWDM) multi-channel performance monitoring is one of the indispensable technologies for the flexible optical networks. The existing Labelbased monitoring scheme requires expensive optical demultiplexing components/equipment to avoid the influence of stimulated Raman scattering (SRS), which is not only costly and bulky, but also could not monitor the wavelength channels simultaneously. In this paper, a low-cost, high-accuracy monitoring scheme based on Optical Label Method is proposed for DWDM networks, where the optical channel power and node identification (ID), as the main monitoring targets that both can indicate or evaluate the channel connection status, could be efficiently monitored. In the scheme, a novel digital signal processing (DSP) method of SRS mitigation is proposed and demonstrated, and an asynchronous code-division multiple access (A-CDMA) based digital label encoding and decoding method is adopted to distinguish the node ID so that channel initial added node can be accurately verified, thereby wavelength connection status can be reliably monitored by combining the channel power and node ID information. The simulation results show that each wavelength channel power and node ID can be accurately monitored only by low bandwidth photoelectric detector (PD) under the condition of 80 wavelengths and 10 spans at C-band.

ALL-OPTICAL CARRY SKIP ADDER WITH THE HELP OF TERAHERTZ OPTICAL ASYMMETRIC DEMULTIPLEXER-BASED SWITCH

The terahertz optical asymmetric demultiplexer (TOAD) or semiconductor optical amplifier (SOA)-assisted Sagnac switches have been used to construct an all-optical 4-bit carry skip adder. This design aims to satisfy the high speed and accuracy requirements of modern ultrafast digital transmission. Using a combination of an all-optical multiplexer and an all-optical full adder, we describe an all-optical carry skip adder. When compared to ripple carry adder and carry look-ahead adder, carry skip adder may be employed to create a fast arithmetical processing unit. Numerical simulation is used to develop and validate this theoretical model.

OPTICAL 4:1 MULTIPLEXER USING SAGNAC SWITCHES

This paper presents the design and implementation of an Optical 4:1 Multiplexer using Sagnac Switches as Terahertz Optical Asymmetric Demultiplexers (TOADs). Optical multiplexers play a crucial role in modern communication systems by combining multiple signals onto a single optical channel. The proposed multiplexer architecture leverages the benefits of Sagnac Switches, such as low insertion loss, high extinction ratio, and low crosstalk, along with TOADs to achieve efficient signal routing and demultiplexing. The design is evaluated through simulations, demonstrating its performance in terms of insertion loss, extinction ratio, and crosstalk. The experimental validation of the multiplexer verifies its effectiveness in real-world scenarios. The Optical 4:1 Multiplexer using Sagnac Switches as TOADs offers a promising solution for optical communication networks, enabling efficient signal multiplexing and demultiplexing while maintaining high data integrity and low signal degradation.

Optical Demultiplexer by Using In-Line Fiber Filter

Optical Demultiplexer by Using In-Line Fiber Filter

A comparative analysis between Drude and Johnson & Christy for nanometric optical demultiplexer

The constant need to miniaturize technological devices has increased the development of novel optical devices in the nanoscale. A common kind of photonic devices are built using Metal-Insulator-Metal (MIM) interfaces to generate Surface Plasmons Polaritons (SPPs) and process light waves in the optical window. In this paper a 12 channel demultiplexer is proposed using 8 cavities coupled to both sides of the main waveguide. Then the nano demultiplexer is modelled in COMSOL Multiphysics using Drude model and Johnson and Christy parameters for the optical constants. Then we compare the transmission spectrum from 400 to 2200 nm for both models and discuss the differences advantages of each method.

Optical Multiplexer

In this paper, we present an all-optical multiplexer based on a Terahertz Optical Asymmetric Demultiplexer (TOAD) device. The TOAD is used as a nonlinear optical switch to selectively route optical signals based on their wavelength or frequency, allowing for the multiplexing of multiple optical channels onto a single fiber optic cable. We describe the design and implementation of the TOAD-based multiplexer, including the optical components and signal processing algorithms used to achieve high-speed, low-error-rate operation. We also present experimental results demonstrating the performance of the multiplexer, including its ability to maintain signal quality over long distances and under various noise and interference conditions. Our results show that the TOAD-based multiplexer offers a promising approach to all-optical multiplexing for high-speed, high-capacity optical communications systems.

A Review on Nonlinearity in Semiconductor optical Amplifer as Application in all Optical Signal Processing

The optical signal processing is the future of communication network. High speed all-optical packet routing is one of the essential applications of all-optical networks which is only possible with the development of all-optical logic technology. The development of optical logic elements and circuits are the steps in the growth of this technology and higher speed up to Tbit/sec can be achieved. The optical carrier frequency range 1013 to 1016 Hz provides enormous potential bandwidth with superior information carrying capacity over a long transmission distance. The need of higher capacity is continuing to encourage research in wavelength division multiplexing (WDM) and optical time division multiplexing (OTDM) based transmission systems, which need optical demultiplexing and wavelength conversion technology. Therefore, for high-speed optical networks, it is required to develop the all-optical gates to avoid power consumption in opto-electronics conversion. All optical logic gates perform computing operations, storage and transmission of data using light also known as optical computing. Optical technology promises massive upgrades in the efficiency and speed of computers, aswell as significant shrinkage in their size and cost. The non-linear optical device to be used i.e. Semiconductor Optical Amplifier (SOA) has proved to be the promising for all optical functions like wavelength conversion, logic functions, signal representation in all optical domain. Its compact size, high gain, fast response, strong refractive index variation, easy to manufacture and integration, and power efficiency makes it most optimum device for optical signal processing. In this paper, the application of SOA in optical processing is thoroughly reviewed and orient towards the latest application in neural networks.

Miniaturized optical vortex mode demultiplexer: Principle, fabrication, and applications

Vortex beams have attracted extensive attention in recent decade due to the carried optical orbital angular momentum (OAM). Vortex beams carrying different OAM modes are orthogonal to each other, and thus have become highly promising in realizing high-capacity optical communication systems. This review is to introduce the fundamental principles of optical OAM mode demultiplexing, recent advances in the fabrication techniques and emerging applications in high-capacity optical communications. First, this review introduces the development history of the working principle of OAM mode demultiplexer. Subsequently, a variety of preparation techniques and emerging applications of OAM mode demultiplexing are discussed in detail. Finally, we provide an in-depth analysis and outlook for the future trends and prospects of the OAM mode demultiplexer.

All optical comparator using tera hertz optical asymmetric demultiplexer (TOAD)

TOAD or Tera Hertz Optical Asymmetric Demultiplexer is an optical switch. Using this switch, we have invented an optical comparator. This optical comparator circuit is very simple in structure with a higher speed (200 Gbps) and finds useful application in optical computation and communication network system. We have simulated all three outputs in detail and shown the eye diagram of all three outputs of the optical comparator. We found high values of extinction ratio (ER), contrast ratio (CR), and quality factor (Q value) for the three outputs of the comparator.

1 × 4 Wavelength Demultiplexer C-Band Using Cascaded Multimode Interference on SiN Buried Waveguide Structure

Back reflection losses are a key problem that limits the performances of optical communication systems that work on wavelength division multiplexing (WDM) technology based on silicon (Si) Multimode Interference (MMI) waveguides. In order to overcome this problem, we propose a novel design for a 1 × 4 optical demultiplexer based on the MMI in silicon nitride (SiN) buried waveguide structure that operates at the C-band spectrum. The simulation results show that the proposed device can transmit four channels with a 10 nm spacing between them that work in the C-band with a low power loss range of 1.98–2.35 dB, large bandwidth of 7.68–8.08 nm, and good crosstalk of 20.9–23.6 dB. Thanks to the low refractive index of SiN, a very low back reflection of 40.57 dB is obtained without using a special angled MMI design, which is usually required, using Si MMI technology. Thus, this SiN demultiplexer MMI technology can be used in WDM technique for obtaining a high data bitrate alongside a low back reflection in optical communication systems.