Few‐Layer Phosphorene‐Decorated Microfiber for All‐Optical Thresholding and Optical Modulation

A novel phased array receive antenna steering system is introduced. The core of this system is an optical ring resonator-hased broadband, continuously tunable optical beam forming network (OBFN). In the proposed system architecture, filter-based optical single-sideband suppressed-carrier modulation and balanced coherent optical detection are used. Such architecture has significant advantages over a straightforward architecture using optical double-sideband modulation and direct optical detection, namely relaxed bandwidth requirements on the optical modulators and detectors, reduced complexity of the OBFN chip, and enhanced dynamic range. Initial measurements on an actual 1 times 8 OBFN chip and an optical sideband filter chip arc presented. Both are realized in CMOS-compatible planar optical waveguide technology.

The technology uses light wave as carrier and optical fiber as transmission medium to realize the function of transmitting information from one end to the other. Optical fiber communication technology has become one of the important means of information transmission in today’s era. It can be imagined that in the near future, optical fiber technology will have more rapid development and application. This paper briefly introduces the principle and characteristics of optical fiber communication technology, analyzes its current application fields, and discusses the future development trend of this technology, so as to let more people understand this technology.

Since the growth of fiber optic communications, extremely low cost optical modules have been expected to be realized. Particularly for the subscriber applications and local area networks (LANs), less than half of past module cost is required. In accordance with the spread of fiber optic transmission, higher volume manufacture is also needed. To attain both of low cost and high productivity, we developed passive alignment technique and optical coupling structure that is suitable for automatic assembly. We also developed automatic assemble equipment for producing several types of optical modules. To reduce optical module cost, it is important to cut down the assembly cost and expensive parts such as optical lens. The passive alignment technique brings us to realize easy assembly of modules and minimize the constructed components of optical coupling. Our mass production techniques include not only for optical coupling but also packaging of the module. We have several types of optical modules according to different fiber communication systems; there are laser modules, detector modules, optical interface modules that are integrated optical coupling and electrical circuit, and PLC (Planar Lightwave Circuit) modules that are integrated passive component. Basically all modules have same optical coupling structure and keep the design rules for automatic assembly. Accordingly, we can use the same equipment for the same assembly process. In this paper, we will introduce basic assembly process and our mass production line for optical coupling and packaging by using passive alignment technique.

ABSTRACTAmidst the next industrial revolution, advanced spaceborne optical communication technologies that offer terabit per second throughput enable seamless exploration, communication, and efficient information capacity allocation. The current paper aims to provide profound insight into the major developments of laser communication activities in deep space. To achieve this objective, a comprehensive review and comparison of the most prominent ESA‐supported (European Space Agency) initiatives, including the Lunar Optical Communication Link (LOCL) and the Deep Space Optical Communications (DSOC) demonstrations, among other activities, are provided. While ESA has gained sophisticated heritage by means of manufacturing and testing a number of cutting‐edge optical communication technologies within LOCL activity, it also intends to demonstrate an augmented ground infrastructure for establishing an end‐to‐end High Photon Efficiency (HPE) optical communication link between Earth and DSOC payload of NASA's (National Aeronautics and Space Administration) Psyche Spacecraft. To this end, critical and leading system designs including specific issues that are required for the realization of next‐generation systems, along with examples of high‐level architectures, are provided in the current work. Considering the enhanced technical expertise, the paper further addresses the technological prospects and envisaged deep‐space optical data‐return channels for future missions, encompassing the giant planets and beyond at distances larger than 4.2 Astronomical Units (AU), as part of the forthcoming planning cycle, Voyage 2050, of ESA's Space Science Programme. All those prominent goals are addressed and evaluated in terms of fundamental limitations that apply to the information capacity of the HPE optical communication system, which is then compared with a radio frequency (RF) Ka‐band link. The demonstrated capabilities to extend the range over 100 AU of optical communication links, while supporting capacity characterized by a high signal‐to‐noise regime, have the potential to revolutionize planetary exploration.

With the exponential growth in demand for transmission based on optical communication technology, providing secure transmission is crucial for the orderly development of individuals and groups in contemporary society. In the context of free-space optical (FSO) communication, we propose and experimentally demonstrate a novel physical layer security transmission scheme based on phase encryption controlled by chaotic sequences. Utilizing the chaotic Chen's equation to generate pseudo-random sequences as keys, we control the modulation of PAM4 signals on phase modulator to achieve phase encryption and decryption of user data. We successfully achieved 10 Gbps NRZ signal transmission over a free-space distance of approximately 3 meters, with a tested bit error rate (BER) lower than the hard-decision forward error correction (HD-FEC) limit. Additionally, we analyzed the influences of various encryption depths, FSO conditions, and delay matching on the system's transmission performance. To the best of our knowledge, this is the first application of chaotic phase encryption in FSO communication scenarios, which will inspire future developments in secure optical communication.

The escalating capacity limitations of conventional near-infrared telecommunication bands have spurred urgent investigations into wide-band optical communication systems spanning from the near-infrared to mid-infrared regimes. This has motivated the development of optical components combining broadband bandwidth with high-speed operation. The state-of-the-art modulators face challenges in achieving broad operational bandwidth due to waveguide dispersion and velocity mismatch. Here we demonstrate a thin-film lithium niobate (TFLN) electro-optic (EO) modulator with an unprecedented 800-nm operational bandwidth, covering the full O-U telecom bands and extending into the 2-μm regime. The TFLN modulator exhibits >67 GHz EO bandwidth across O-U bands (~100 GHz at O-/S-/C-/L-bands) and >50 GHz at 2-μm band. It enables single-lane exceeding 240 Gbps PAM-4 transmission across O-U bands and a record 170 Gbps PAM-4 transmission at 2-μm band. This breakthrough establishes TFLN as a compelling platform for multispectral photonics, bridging conventional telecom infrastructure with emerging 2-μm technologies for next-generation optical communications.

As an important application of laser technology, optical fiber communications are key enablers for the current information age. With the emergence of new technologies including Internet of Things, big data, cloud computing, virtual reality, and artificial intelligence, there are growing needs in the society for high capacity information transmission, which puts forward higher requirements for the optical fiber communication technology. Based on a systematic review of the development status of the technology in China and abroad, this paper analyzes the problems and challenges it faces in the application of specific scenarios, and prospects the development of some related technologies in the future. Through analysis, the challenges in optical fiber communication systems with an ultra-large capacity can be solved by increasing the transmitted power, raising the bandwidth of optical amplifiers, and conducting research on low-loss optical fibers and technologies related to space division multiplexing. The cost problems of the systems in other scenarios are also considered. In general, the optical fiber communication technology is evolving toward the direction of ultra-large capacity, intelligence, and integration. It is hoped to realize intelligent monitoring of network parameters, as well as ultra-long distance and ultra-large capacity transmission. With the development of devices and integration technology, the optical fiber communication industry continues to move forward toward the goal of high performance and low cost.

As human society to the information in the process of moving and growing demand for bandwidth communications capacity, the optical of new modulation formats increasingly attention and quickly play an important role in optical communications. How can the system bit error rate within a certain degree of stability while still maintaining high-speed long-distance dispersal system, has been a popular issue is the optical communications industry. Starting from the optical modulation format herein, the generation process of the system introduced various optical signal modulation format, the optical signal through the optical fiber was studied and the performance of the simulation, on the basis of the design of advanced optical modulation formats in an optical fiber communication system .

Multiple-layer perovskite Pb/sub 0.91/La/sub 0.09/Zr/sub 0.65/Ti/sub 0.35/O/sub 3//SrTiO/sub 3/ (PLZT/STO) heterostructures have been grown by pulsed laser deposition (PLD) on [001] MgO/GaAs substrates. The perovskite layers are single phase with 35nm RMS roughness on the top surface. Electrically induced birefringence in the PLZT layers, resulted in both optical phase and optical amplitude modulation. The application of an electric field across the PLZT layers resulted in optical modulation at both the primary and first harmonic frequencies, and direct evidence of the non-linear electro-optic effect.

While thin-film lithium niobate (TFLN) is known for efficient signal generation, on-chip signal amplification remains challenging from fully integrated optical communication circuits. Here we demonstrate the continuous-wave-pump optical parametric amplification (OPA) using an x-cut domain-engineered TFLN waveguide, with high gain over the telecom band up to 13.9 dB, and test it for high signal-to-noise ratio signal amplification using a commercial optical communication module pair. Fabricated in wafer scale using a process that is common for devices including modulators, this OPA device marks an important step in TFLN photonic integration.

With the development of information age, the optical fiber communication network has also been greatly developed, and a large number of optical fiber systems should be shipped. Wavelength division multiplexing technology has become the most important technology in optical communication, which has a strong practical significance. The aim of this paper is to design and analyze the digital optical communication system by using the optical system. Using the most suitable configuration, including the optical transmission system at 1310nm and 1550nm wavelength as input power, using single-mode and multi-mode fiber as transmission, using zeroing code and non-zeroing code for modulation and demodulation system to code information, so as to maximize the spectral efficiency of the whole system. There are three evaluation indexes, including signal output power, signal noise spectrum, and transmission rate of two kinds of optical fiber.

Surprisingly, nano-photonic silicon has already emerged as a commercial INTER-chip optical communications technology. This was made possible by Silicon-on-Insulator (SOI), technology, which integrates many of the optical communications components directly in silicon CMOS chips. Intel and Luxtera have both announced > 10Gb/sec optical modulators, integrated into Silicon. All the other customarily required opto-electronic components; detectors, waveguides, splitters, couplers, filters, etc., are fully executed in CMOS designs, as well. Continuous wave optical power is provided from off-chip, just as dc power is currently provided from off-chip. The initial commercial applications are optical 10Gb/s Ethernet, Infiniband, and other INTER-chip, communications applications. The question to be addressed in this talk, is whether silicon nano-photonics can now make the final jump, to INTRA-chip optical interconnects?

The recent challenges for improving the operation speed of nanoelectronics have motivated research on manipulating light in on-chip integrated circuits. Hybrid plasmonic waveguides with low-dimensional semiconductors, including quantum dots and quantum wells, are a promising platform for realizing sub-diffraction limited optical components. Meanwhile, two-dimensional transition metal dichalcogenides (TMDs) have received broad interest in optoelectronics owing to tightly bound excitons at room temperature, strong light-matter and exciton-plasmon interactions, available top-down wafer-scale integration, and band-gap tunability. Here, we demonstrate principal functionalities for on-chip optical communications via reconfigurable exciton-plasmon interconversions in ∼200-nm-diameter Ag-nanowires overlapping onto TMD transistors. By varying device configurations for each operation purpose, three active components for optical communications are realized: field-effect exciton transistors with a channel length of ∼32 μm, field-effect exciton multiplexers transmitting multiple signals through a single NW and electrical detectors of propagating plasmons with a high On/Off ratio of∼190. Our results illustrate the unique merits of two-dimensional semiconductors for constructing reconfigurable device architectures in integrated nanophotonic circuits.

Optical satellite communication with the advantages of broadband, large capacity and low power consuming broke the bottleneck of the traditional microwave satellite communication. The formation of the Space-based Information System with the technology of high performance optical inter-satellite communication and the realization of global seamless coverage and mobile terminal accessing are the necessary trend of the development of optical satellite communication. Considering the resources, missions and restraints of Data Relay Satellite Optical Communication System, a model of optical communication resources scheduling is established and a scheduling algorithm based on artificial intelligent optimization is put forwarded. According to the multi-relay-satellite, multi-user-satellite, multi-optical-antenna and multi-mission with several priority weights, the resources are scheduled reasonable by the operation: “Ascertain Current Mission Scheduling Time” and “Refresh Latter Mission Time-Window”. The priority weight is considered as the parameter of the fitness function and the scheduling project is optimized by the Genetic Algorithm. The simulation scenarios including 3 relay satellites with 6 optical antennas, 12 user satellites and 30 missions, the simulation result reveals that the algorithm obtain satisfactory results in both efficiency and performance and resources scheduling model and the optimization algorithm are suitable in multi-relay-satellite, multi-user-satellite, and multi-optical-antenna recourses scheduling problem.

Optical fiber communication technology is beneficial to satisfy today's increasing demands for high data rates. This need for higher data rates and bandwidth has driven the fast development of fiber optic communication technologies. But at the same time, some undesirable nonlinear effects in the optical fiber medium become noticeable at high power levels. These fiber nonlinearities affect the optical fiber communication systems. The light signal in Wavelength Division Multiplexing (WDM) system can be degraded due to nonlinear impairments in the fiber. So it has become necessary to study the nonlinear effects. In this paper, nonlinear effects called Self-Phase Modulation (SPM) and Four-Wave Mixing (FWM) are observed. Factors responsible for variations in SPM and FWM effects are analyzed using OptiSystem simulation tool.