Advances In Optical Communications Research Articles

Broadband multifunctional metasurfaces for concentric perfect vortex beam generation via trigonometric functions

Metasurfaces are engineered structures that offer an unprecedented nanoscale solution for precisely manipulating light’s magnitude, phase, and polarization, exhibiting the potential to reduce the size of optical configurations significantly. However, these structures often encounter performance limitations and are typically operational for a single design wavelength. Integrating multiple optical functionalities into a single-layered structure and achieving a highly efficient broadband response is an active metasurface research topic. In this study, we showcased a single-cell driven broadband metasurface capable of generating concentric perfect vortex (PV) beams, where each PV beam is realized by multiplexing the phase profiles of multiple optical components and trigonometric phase features to achieve infinite topological charges. The proposed all-silicon metasurface demonstrates broadband functionality in “E” and “S” optical communication bands spanning from 1460 nm to 1565 nm, covering critical telecom wavelengths, and this characteristic facilitates seamless integration of our work with the existing ecosystem. Our multifunctional approach prioritizes simplicity that yields maximum polarization conversion efficiency and produces different outcomes for different handedness of incident light without introducing complexity. To prove the concept, we numerically simulated multiple metasurfaces for different trigonometric functions, with periods of axicon of 4 µm and 6 µm. The results indicate that this work will pave the way for diverse applications like optical trapping, particle manipulation, quantum processing, optical communication, and high-capacity information processing.

Series Editorial: Optical Communications and Networks

In the first issue of the Optical Communications and Networks Series in 2023, we have selected six fascinating articles reporting on recent advances in optical communications and networking. They address free-space optical (FSO) communications including visible light communication (VLC), intelligent fiber-optic communications leveraging machine learning (ML), passive optical network (PON) technology for industrial networks, and dynamic optical path provisioning for alien access links.

Series Editorial: Optical Communications and Networks

In the third issue of the Optical Communications and Networks Series in 2022, we have selected three intriguing articles reporting on recent advances in optical communications and networking.

Special issue “optical communications, sensing, and laser applications”

Special issue “optical communications, sensing, and laser applications”

Series Editorial: Optical Communications and Networks

In the second issue of the Optical Communications and Networks Series in 2022, we have selected two articles that present recent advances in optical communications and networking. These advances and innovations are aimed at making the optical infrastructure of the future Internet more intelligent and secure. More specifically, the two contributions selected address the applicability of physics-informed neural network (PINN) in optical fiber communication and quantum key distribution (QKD) chaining for large-scale quantum networks.

Compound Meta-Optics for Complete and Loss-Less Field Control.

Optical metasurfaces offer a compact platform for manipulation of the amplitude, phase, and polarization state of light. Independent control over these properties, however, is hindered by the symmetric transmission matrix associated with single-layer metasurfaces. Here, we utilize multilayer birefringent meta-optics to realize high-efficiency, independent control over the amplitude, phase, and polarization state of light. High-efficiency control is enabled by redistributing the wavefront between cascaded metasurfaces, while end-to-end inverse design is used to realize independent complex-valued functions for orthogonal polarization states. Based on this platform, we demonstrate spatial mode division multiplexing, optical mode conversion, and universal vectorial holograms, all with diffraction efficiencies over 80%. This meta-optic platform expands the design space of flat optics and could lead to advances in optical communications, quantum entanglement, and information encryption.

Series Editorial: Optical Communications and Networks

In the first issue of the Optical Communications and Networks Series in 2022, we have selected three articles that present recent advances in optical communications and networking. These advances and innovations are aimed at realizing higher-speed communication in various applications. More specifically, the three contributions selected demonstrate advances in passive optical networks (PONs), hybrid visible light communication (VLC) and radio frequency (RF) systems, and optical data center networks (DCNs) enabled by synergistic switch control.

Silicon-Based Graphene Electro-Optical Modulators

With the increasing demand for capacity in communications networks, the use of integrated photonics to transmit, process and manipulate digital and analog signals has been extensively explored. Silicon photonics, exploiting the complementary-metal-oxide-semiconductor (CMOS)-compatible fabrication technology to realize low-cost, robust, compact, and power-efficient integrated photonic circuits, is regarded as one of the most promising candidates for next-generation chip-scale information and communication technology (ICT). However, the electro-optic modulators, a key component of Silicon photonics, face challenges in addressing the complex requirements and limitations of various applications under state-of-the-art technologies. In recent years, the graphene EO modulators, promising small footprints, high temperature stability, cost-effective, scalable integration and a high speed, have attracted enormous interest regarding their hybrid integration with SiPh on silicon-on-insulator (SOI) chips. In this paper, we summarize the developments in the study of silicon-based graphene EO modulators, which covers the basic principle of a graphene EO modulator, the performance of graphene electro-absorption (EA) and electro-refractive (ER) modulators, as well as the recent advances in optical communications and microwave photonics (MWP). Finally, we discuss the emerging challenges and potential applications for the future practical use of silicon-based graphene EO modulators.

Series Editorial: Optical Communications and Networks

In this second issue of the Optical Communications and Networks Series in 2021, we have selected three articles that present recent advances in optical communications and networking. These advances and innovations are aimed at making the optical infrastructure of future Internet more secure, energy-efficient, and intelligent.

Guest Editorial: Transport Layer Innovations for Future Networks

The communication technologies used for Internet connectivity have radically changed since the 1980s, when the current design of the TCP/IP stack was introduced. Most of the traffic will soon be generated by mobile devices, connected to different generations of wireless networks, which now can provide to end users a multi-gigabit-per-second data rate. Mobile devices are more and more heterogeneous, and support connectivity over different interfaces and networks. Similarly, the capacity of fixed and backhaul networks has dramatically increased, thanks to advances in optical communications.

Optical Communications and Networks

The articles in this special section focus on optical communications and networks. These articles present the most recent advances in optical communications and networking. These advances and innovations are aimed at making the optical infrastructure of the future Internet more secure, energy-efficient, universal, and intelligent.

Disaggregated Data Centers: Challenges and Trade-offs

Disaggregated data centers (DCs) can offer high flexibility for resource allocation; hence, their resource utilization can be significantly improved. However, communications between different types of resources, in particular between CPU and memory, in fully disaggregated DCs face severe problems in terms of stringent requirements for ultra-low latency and ultra-high transmission bandwidth. Optical fiber communication is promising to provide high capacity and low latency, but it is still challenging for the state-of-the-art optical technologies to meet the requirements of fully disaggregated DCs. In this article, different levels of resource disaggregation are investigated. For fully disaggregated DCs, two architectural options are presented, where optical interconnects are necessary for the CPU-memory communications. We review the state-of-the-art optical transmission and switching technologies, and analyze pros and cons of their applicability in the disaggregated DCs. The results reveal that resource disaggregation does improve the resource utilization in DCs. However, the bandwidth provided by the state-of-the-art technologies is not always sufficient for fully disaggregated DCs. It calls for further advances in optical communications to fully utilize the advantages of fully disaggregated DCs.

Advances in Optical Communications and Network Technologies

The four articles in this special section focus on advancements in optical communications and network technologies. In 2019, optical communications and networking technologies continue to gain momentum to facilitate innovations in various networks, including not only metro and core but also access and data center networks. Moreover, we are beginning to see the applications of machine learning (ML) and artificial intelligence (AI) in these networks, aiming to make them more intelligent, adaptive, and agile. Specifically, ML and AI refer to a broad range of approaches that work with statistical data models, with which computers can solve complex optimization problems without being explicitly programmed. Considering the complexity associated with managing optical communications and networking systems and the need to make it easier, we expect to see more advances in the field of applying ML and AI for managing optical networks and systems in the coming years.

Advances in Optical Communications and Networking Technologies

Advances in Optical Communications and Networking Technologies

Advances in communications using optical vortices

An optical vortex having an isolated point singularity is associated with the spatial structure of light waves. A polarization vortex (vector beam) with a polarization singularity has spatially variant polarizations. A phase vortex with phase singularity or screw dislocation has a spiral phase front. The optical vortex has recently gained increasing interest in optical trapping, optical tweezers, laser machining, microscopy, quantum information processing, and optical communications. In this paper, we review recent advances in optical communications using optical vortices. First, basic concepts of polarization/phase vortex modulation and multiplexing in communications and key techniques of polarization/phase vortex generation and (de)multiplexing are introduced. Second, free-space and fiber optical communications using optical vortex modulation and optical vortex multiplexing are presented. Finally, key challenges and perspectives of optical communications using optical vortices are discussed. It is expected that optical vortices exploiting the space physical dimension of light waves might find more interesting applications in optical communications and interconnects.

A survey on recent advances in optical communications

Recent advances in optical communications not only increase the capacities of communication system but also improve the system dynamicity and survivability. Various new technologies are invented to increase the bandwidth of individual wavelength channels and the number of wavelengths transmitted per fiber. Multiple access technologies have also been developed to support various emerging applications, including real-time, on-demand and high data-rate applications, in a flexible, cost effective and energy efficient manner.In this paper, we overview recent research in optical communications and focus on the topics of modulation, switching, add-drop multiplexer, coding schemes, detection schemes, orthogonal frequency-division multiplexing, system analysis, cross-layer design, control and management, free space optics, and optics in data center networks. The primary purpose of this paper is to refresh the knowledge and broaden the understanding of advances in optical communications, and to encourage further research in this area and the deployment of new technologies in production networks.

Advances in optical communications [Series Editorial

The global optical communications industry has continued to show progress through the first half of 2013. Although optical access network deployments have been slower, we have been witnessing steady progress in fiber-based broadband access network growth. Communications service providers have continued their deployment of high-speed (100G and beyond) transport networks, and have been participating in field trials of higher-speed optical transport network equipment and systems.

Advances in optical communications

Advances in optical communications

Advances in optical communications in the RACE programme

This special issue of Optical and Quantum Electronics is well-timed for reviewing the work of the RACE Programme (Research and development of Advanced Communications in Europe). RACE has as its overall objective the 'Introduction of IBC (Integrated Broadband Communication), taking into account the evolving ISDN and National introduction strategies, progressing to Community-wide services by 1995'. RACE Phase 1, which was a 5-year programme, finished at the end of 1992. The work in the Phase 2 Projects is now well under way, with the first-year work programme now completed [1], having started in January 1992 in most cases. The formulation of the European Commission's Fourth Framework Programme for Research and Development (1994-8) is now in progress. It is therefore timely to consider the final outcome of RACE 1 and to look for progress reports of RACE 2. Optical technology development is of key importance to the RACE programme. Optical fibre provides an infrastructure that is capable of supporting existing and future broadband services. Such services include teleworking, videotelephony and multimedia, in addition to telephony and television distribution. The major role of optics can be seen from the number of projects involved; 18 of the 93 projects in Phase 1 and 21 of the 95 projects in Phase 2 are concerned with optical technology. The work programmes in these projects cover the complete spectrum of research and development, from basic materials research to field demonstrations of 'fibre-tothe-customer'. The partners in a project may include public network operators, academic institutions, equipment manufacturers, service providers and users. The breadth of coverage of the work is reflected in the titles of the papers included in this special issue, and their authors. The Workplan of the RACE programme has been formulated to obtain coherent coverage of the range of necessary activities and to make sure that these activities are properly coordinated. For example, new components are not developed in isolation; the relevant systems applications are taken into account and a real need must be identified. The particular needs of the services that the optical fibre infrastructure will support need to be carefully analysed and the impact on network topology needs to be assessed. On the other hand, it is recognized that it is not always possible to predict where the next breakthrough will come from; it is necessary to have some degree of flexibility in the investigation of basic research topics. The full list of RACE 2 Optical Projects is given in Table I and the interrelations between the projects and areas of coverage are illustrated in Fig. 1.