scholarly journals Graphene on Silicon Photonics: Light Modulation and Detection for Cutting-Edge Communication Technologies

2021 ◽  
Vol 12 (1) ◽  
pp. 313
Author(s):  
Siqi Yan ◽  
Jeremy Adcock ◽  
Yunhong Ding
Keyword(s):  
Silicon Photonics ◽  
Communication Systems ◽  
High Performance ◽  
Low Cost ◽  
Single Layer ◽  
Photonic Devices ◽  
Optoelectronic Properties ◽  
Propagation Loss ◽  
Honeycomb Lattice ◽  
Light Modulation

Graphene—a two-dimensional allotrope of carbon in a single-layer honeycomb lattice nanostructure—has several distinctive optoelectronic properties that are highly desirable in advanced optical communication systems. Meanwhile, silicon photonics is a promising solution for the next-generation integrated photonics, owing to its low cost, low propagation loss and compatibility with CMOS fabrication processes. Unfortunately, silicon’s photodetection responsivity and operation bandwidth are intrinsically limited by its material characteristics. Graphene, with its extraordinary optoelectronic properties has been widely applied in silicon photonics to break this performance bottleneck, with significant progress reported. In this review, we focus on the application of graphene in high-performance silicon photonic devices, including modulators and photodetectors. Moreover, we explore the trend of development and discuss the future challenges of silicon-graphene hybrid photonic devices.

Design and analysis of CPW-fed compact planar antennas for ultra wideband communication systems

2016 ◽  
Author(s):  
◽  
Haitham Alsaif
Keyword(s):  
Communication Systems ◽  
High Performance ◽  
Low Cost ◽  
Single Layer ◽  
Ultra Wideband ◽  
University Of Missouri ◽  
Uwb Antennas ◽  
Operating Frequency Range ◽  
Performance Results ◽  
Compact Planar

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] In this research, three new designs of planar compact ultra-wideband (UWB) antennas have been studied, simulated, and experimentally measured. Their structures are not complicated in design, easy in fabrication with low cost. They are in different physical sizes and considered small compared to many recent published UWB antennas that have similar performance. The proposed antennas have ultra-wide bandwidth that cover the entire bandwidth allocated by FCC for such applications. They are made to be planar structure with a single layer in order to be easier in fabrication and for use in wireless devices and applications. The used feeding technique is coplanar wave-guide (CPW) in all of them due to the great advantages of this feeding methodology. Each design has certain more superiority over the others either in terms of operating frequency range, power gain, radiation pattern, or structure size. Although, all compact patch antennas demonstrate high performance results and are very suitable for ultra-wideband systems. Finally, since there are a variety of ultra-wideband applications with several characteristics requirements, the research is composed of three different sizes of compact planar single layers antennas. These antennas have similar or better performance than some other large size designs, which makes it suitable for very compact wireless gadgets. Thus, the ultra-wideband (UWB) systems designer will be able to select the most appropriate design for the application based on the antenna characterizes and size.

Surface Passivation by Congeneric Quantum Dots for High-Performance and Stable CsPbBr3-Based Photodetectors

2021 ◽  
Author(s):  
Shikai Yan ◽  
Sheng Tang ◽  
Manman Luo ◽  
Lu Xue ◽  
Shilin Liu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
High Performance ◽  
Surface Passivation ◽  
Low Cost ◽  
Optoelectronic Properties ◽  
Solution Processing

CsPbBr3-based photodetectors (PDs) have aroused enormous attention owing to their low-cost solution processing, outstanding optoelectronic properties, and remarkable stability. However, their performances remain a big challenge to meet the requirement...

scholarly journals 2D MoS2 Encapsulated Silicon Nanopillar Array with High-Performance Light Trapping Obtained by Direct CVD Process

Crystals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 267
Author(s):  
Minyu Bai ◽  
Zhuoman Wang ◽  
Jijie Zhao ◽  
Shuai Wen ◽  
Peiru Zhang ◽  
...  
Keyword(s):  
Silicon Substrate ◽  
High Performance ◽  
Low Cost ◽  
Light Trapping ◽  
Incident Light ◽  
Single Layer ◽  
Chemical Vapor ◽  
Optoelectronic Device ◽  
Planar Silicon ◽  
Shortwave Infrared

Weak absorption remains a vital factor that limits the application of two-dimensional (2D) materials due to the atomic thickness of those materials. In this work, a direct chemical vapor deposition (CVD) process was applied to achieve 2D MoS2 encapsulation onto the silicon nanopillar array substrate (NPAS). Single-layer 2D MoS2 monocrystal sheets were obtained, and the percentage of the encapsulated surface of NPAS was up to 80%. The reflection and transmittance of incident light of our 2D MoS2-encapsulated silicon substrate within visible to shortwave infrared were significantly reduced compared with the counterpart planar silicon substrate, leading to effective light trapping in NPAS. The proposed method provides a method of conformal deposition upon NPAS that combines the advantages of both 2D MoS2 and its substrate. Furthermore, the method is feasible and low-cost, providing a promising process for high-performance optoelectronic device development.

scholarly journals Design and Analysis of a Photonic Crystal Based Planar Antenna for THz Applications

Electronics ◽  
2021 ◽  
Vol 10 (16) ◽  
pp. 1941
Author(s):  
Inzamam Ahmad ◽  
Sadiq Ullah ◽  
Shakir Ullah ◽  
Usman Habib ◽  
Sarosh Ahmad ◽  
...  
Keyword(s):  
Communication Systems ◽  
High Speed ◽  
Low Cost ◽  
High Gain ◽  
Propagation Loss ◽  
Smart Devices ◽  
Frequency Range ◽  
Low Profile ◽  
Unit Cells ◽  
Thz Applications

Modern advancements in wearable smart devices and ultra-high-speed terahertz (THz) communication systems require low cost, low profile, and highly efficient antenna design with high directionality to address the propagation loss at the THz range. For this purpose, a novel shape, high gain antenna for THz frequency range applications is presented in this work. The proposed antenna is based on a photonic bandgap (PBG)-based crystal polyimide substrate which gives optimum performance in terms of gain (9.45 dB), directivity (9.99 dBi), and highly satisfactory VSWR (<1) at 0.63 THz. The performance of the antenna is studied on PBGs of different geometrical configurations and the results are compared with the antenna based on the homogeneous polyimide-based substrate. The effects of variations in the dimensions of the PBG unit cells are also studied to achieve a −10 dB bandwidth of 28.97 GHz (0.616 to 0.64 THz).

scholarly journals Bidirectional Angle-Tolerant Polarization-Tuned Filtering and Wide-Range Refractive Index Sensing Based on Metal Film Coated Nanograting

Nanomaterials ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 47
Author(s):  
Wenli Cui ◽  
Qiannan Wu ◽  
Bo Chen ◽  
Xufeng Li ◽  
Xiaolin Luo ◽  
...  
Keyword(s):  
Refractive Index ◽  
Metal Film ◽  
High Performance ◽  
Incident Angle ◽  
Single Layer ◽  
Transverse Magnetic ◽  
Photonic Devices ◽  
Biomedical Sensors ◽  
Dual Channel ◽  
Wide Range

The miniaturization and integration of photonic devices are new requirements in the fast-growing optics field. In this paper, we focus on a feature-rich sub-wavelength nanograting-coated single-layer metal film. The numerical results show that the reflection behaviors of this proposed structure can realize bidirectional dual-channel ultra-narrowband polarized filtering and bidirectional wavelength-modulated sensing in a wide refractive index (RI) range from 1.0 to 1.4 for incident angle of 10° with transverse-magnetic (TM) polarized illumination at wavelengths between 550 nm to 1500 nm. Moreover, the bidirectional properties of filtering and sensing are not obviously decreased when increasing incident angle from 10° to 30°, and decreasing incident angle from 10° to 0°. The calculated RI sensitivity can be up to 592 nm/RIU with a high figure of merit (FOM) of 179.4 RIU−1. More to the point, this nanograting has a simple structure and is less sensitive to the height and shape of grating ridge, which provides great convenience for the fabrication of devices. The other thing that is going on is that this structure can also realize synchronously tunable color filtering, including green to red, with high color purity in the visible band by choosing the period. The underlying physical mechanism is analyzed in detail, and is primarily attributed to surface plasmon polariton (SPP) resonance and dipole resonance at double plasmon resonance wavelengths. This work has tremendous potential in developing multipurpose and high-performance integrated optical devices such as spectral filters, colored displays and plasmon biomedical sensors.

scholarly journals Subwavelength silicon photonics for on-chip mode-manipulation

PhotoniX ◽  
2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Chenlei Li ◽  
Ming Zhang ◽  
Hongnan Xu ◽  
Ying Tan ◽  
Yaocheng Shi ◽  
...  
Keyword(s):  
Silicon Photonics ◽  
High Performance ◽  
Photonic Devices ◽  
Multimode Waveguide ◽  
Plasmonic Waveguides ◽  
Mode Dispersion ◽  
Integrated Devices ◽  
Power Splitters ◽  
On Chip ◽  
Modal Field

AbstractOn-chip mode-manipulation is one of the most important physical fundamentals for many photonic integrated devices and circuits. In the past years, great progresses have been achieved on subwavelength silicon photonics for on-chip mode-manipulation by introducing special subwavelength photonic waveguides. Among them, there are two popular waveguide structures available. One is silicon hybrid plasmonic waveguides (HPWGs) and the other one is silicon subwavelength-structured waveguides (SSWGs). In this paper, we focus on subwavelength silicon photonic devices and the applications with the manipulation of the effective indices, the modal field profiles, the mode dispersion, as well as the birefringence. First, a review is given about subwavelength silicon photonics for the fundamental-mode manipulation, including high-performance polarization-handling devices, efficient mode converters for chip-fiber edge-coupling, and ultra-broadband power splitters. Second, a review is given about subwavelength silicon photonics for the higher-order-mode manipulation, including multimode converters, multimode waveguide bends, and multimode waveguide crossing. Finally, some emerging applications of subwavelength silicon photonics for on-chip mode-manipulation are discussed.

scholarly journals Graphene-Assisted Polymer Waveguide Optically Controlled Switch Using First-Order Mode

Polymers ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 2117
Author(s):  
Yue Yang ◽  
Jiawen Lv ◽  
Baizhu Lin ◽  
Yue Cao ◽  
Yunji Yi ◽  
...  
Keyword(s):  
Power Consumption ◽  
Communication Systems ◽  
Switching Time ◽  
Ohmic Heating ◽  
Low Cost ◽  
Optical Signal ◽  
Propagation Loss ◽  
Polymer Materials ◽  
Pump Light ◽  
All Optical

All-optical devices have a great potential in optical communication systems. As a new material, graphene has attracted great attention in the field of optics due to its unique properties. We propose a graphene-assisted polymer optically controlled thermo-optic switch, based on the Ex01 mode, which can reduce the absorption loss of graphene. Graphene absorbs 980 nm pump light, and uses the heat generated by ohmic heating to switch on and off the signal light at 1550 nm. The simulation results show that, when the graphene is in the right position, we can obtain the power consumption of 9.5 mW, the propagation loss of 0.01 dB/cm, and the switching time of 127 μs (rise)/125 μs (fall). The switching time can be improved to 106 μs (rise) and 102 μs (fall) with silicon substrate. Compared with an all-fiber switch, our model has lower power consumption and lower propagation loss. The proposed switch is suitable for optically controlled fields with low loss and full polarization. Due to the low cost and easy integration of polymer materials, the device will play an important role in the fields of all-optical signal processing and silicon-based hybrid integrated photonic devices.

HYBRID SOL-GEL ELECTRO-OPTIC POLYMER MODULATORS: BEATING THE DRIVE VOLTAGE/LOSS TRADEOFF

2007 ◽  
Vol 16 (02) ◽  
pp. 217-230 ◽  
Author(s):  
R. A. NORWOOD ◽  
C. DEROSE ◽  
Y. ENAMI ◽  
H. GAN ◽  
C. GREENLEE ◽  
...  
Keyword(s):  
Insertion Loss ◽  
High Speed ◽  
Molecular Design ◽  
Low Cost ◽  
Sol Gel ◽  
Single Layer ◽  
Propagation Loss ◽  
Scattering Loss ◽  
Electro Optic ◽  
Polymer Modulators

There has been great progress in the development of electro-optic (EO) polymers with exceptionally high r33 coefficients, with values ranging from 100–400 pm/V now being reported for single layer electro-optic polymer films. While this enables the fabrication of EO modulators with sub-volt operation, it is also necessary to make devices with acceptably low insertion loss (< 6 dB) in order to compete with existing technology. We have developed a solution to the voltage/insertion loss tradeoff in EO polymer modulators by adopting a hybrid geometry that provides for low optical coupling loss, electro-optic polymer limited propagation loss, highly efficient poling, and low cost fabrication. This combination of properties has allowed us to achieve r 33 = 170 pm/V in an EO phase modulator. In addition to this proven approach to optimizing the figure of merit, there are several other approaches that can have high impact. The development of low loss EO polymer and cladding materials and waveguides can greatly reduce the insertion loss of EO polymer modulators, through chemical substitution techniques such as selective halogenation, as well as through improved processing to reduce roughness, stress and poling induced losses. Halogenation can be used to reduce the number of C – H bonds, which have well-known stretch and bend vibrational modes whose overtones extend into the optical communications bands at 1550 nm and 1310 nm. While roughness and stress effects are well-understood from work on passive waveguides, the poling process can produce inhomogeneities that lead to increased scattering loss; molecular design can be used to reduce poling induced loss. Another approach is to adopt non-waveguide device formats that are more tolerant of material losses, such as Fabry-Perot etalons. While etalons may not be viable for very high speed applications (i.e., GHz regime), they present entirely new application areas for electro-optic polymers.

scholarly journals Grating Couplers on Silicon Photonics: Design Principles, Emerging Trends and Practical Issues

Micromachines ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 666 ◽  
Author(s):  
Lirong Cheng ◽  
Simei Mao ◽  
Zhi Li ◽  
Yaqi Han ◽  
H. Fu
Keyword(s):  
Optical Fibers ◽  
Silicon Photonics ◽  
High Performance ◽  
Low Cost ◽  
Coupling Efficiency ◽  
Polarization Sensitivity ◽  
Grating Couplers ◽  
Space Optics ◽  
Wavelength Sensitivity ◽  
Out Of Plane

Silicon photonics is an enabling technology that provides integrated photonic devices and systems with low-cost mass manufacturing capability. It has attracted increasing attention in both academia and industry in recent years, not only for its applications in communications, but also in sensing. One important issue of silicon photonics that comes with its high integration density is an interface between its high-performance integrated waveguide devices and optical fibers or free-space optics. Surface grating coupler is a preferred candidate that provides flexibility for circuit design and reduces effort for both fabrication and alignment. In the past decades, considerable research efforts have been made on in-plane grating couplers to address their insufficiency in coupling efficiency, wavelength sensitivity and polarization sensitivity compared with out-of-plane edge-coupling. Apart from improved performances, new functionalities are also on the horizon for grating couplers. In this paper, we review the current research progresses made on grating couplers, starting from their fundamental theories and concepts. Then, we conclude various methods to improve their performance, including coupling efficiency, polarization and wavelength sensitivity. Finally, we discuss some emerging research topics on grating couplers, as well as practical issues such as testing, packaging and promising applications.

Sign in / Sign up

Export Citation Format

Share Document