A review of silicon subwavelength gratings: building break-through devices with anisotropic metamaterials

Nanophotonics ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
José Manuel Luque-González ◽  
Alejandro Sánchez-Postigo ◽  
Abdelfettah Hadij-ElHouati ◽  
Alejandro Ortega-Moñux ◽  
J. Gonzalo Wangüemert-Pérez ◽  
...  
Keyword(s):  
Silicon Photonics ◽  
High Speed ◽  
Subwavelength Structures ◽  
Silicon Waveguides ◽  
Subwavelength Gratings ◽  
Artificial Materials ◽  
Depth Analysis ◽  
And Performance ◽  
Quantum Photonics ◽  
Improve Device

Abstract Silicon photonics is playing a key role in areas as diverse as high-speed optical communications, neural networks, supercomputing, quantum photonics, and sensing, which demand the development of highly efficient and compact light-processing devices. The lithographic segmentation of silicon waveguides at the subwavelength scale enables the synthesis of artificial materials that significantly expand the design space in silicon photonics. The optical properties of these metamaterials can be controlled by a judicious design of the subwavelength grating geometry, enhancing the performance of nanostructured devices without jeopardizing ease of fabrication and dense integration. Recently, the anisotropic nature of subwavelength gratings has begun to be exploited, yielding unprecedented capabilities and performance such as ultrabroadband behavior, engineered modal confinement, and sophisticated polarization management. Here we provide a comprehensive review of the field of subwavelength metamaterials and their applications in silicon photonics. We first provide an in-depth analysis of how the subwavelength geometry synthesizes the metamaterial and give insight into how properties like refractive index or anisotropy can be tailored. The latest applications are then reviewed in detail, with a clear focus on how subwavelength structures improve device performance. Finally, we illustrate the design of two ground-breaking devices in more detail and discuss the prospects of subwavelength gratings as a tool for the advancement of silicon photonics.

scholarly journals Silicon photonics devices for integrated analog signal processing and sampling

Nanophotonics ◽  
2014 ◽  
Vol 3 (4-5) ◽  
pp. 313-327 ◽  
Author(s):  
Steven Spector ◽  
Cheryl Sorace-Agaskar
Keyword(s):  
Signal Processing ◽  
Silicon Photonics ◽  
High Speed ◽  
Analog Signal Processing ◽  
Photonic Devices ◽  
Analog Signal ◽  
Optical Systems ◽  
Analog To Digital ◽  
And Performance ◽  
Analog Systems

AbstractSilicon photonics offers the possibility of a reduction in size weight and power for many optical systems, and could open up the ability to build optical systems with complexities that would otherwise be impossible to achieve. Silicon photonics is an emerging technology that has already been inserted into commercial communication products. This technology has also been applied to analog signal processing applications. MIT Lincoln Laboratory in collaboration with groups at MIT has developed a toolkit of silicon photonic devices with a focus on the needs of analog systems. This toolkit includes low-loss waveguides, a high-speed modulator, ring resonator based filter bank, and all-silicon photodiodes. The components are integrated together for a hybrid photonic and electronic analog-to-digital converter. The development and performance of these devices will be discussed. Additionally, the linear performance of these devices, which is important for analog systems, is also investigated.

scholarly journals Low-Cost 400 Gbps DR4 Silicon Photonics Transmitter for Short-Reach Datacenter Application

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1941
Author(s):  
Haike Zhu ◽  
Sean Anderson ◽  
Nick Karfelt ◽  
Lingjun Jiang ◽  
Yunchu Li ◽  
...  
Keyword(s):  
Form Factor ◽  
Silicon Photonics ◽  
High Speed ◽  
Low Cost ◽  
Optical Components ◽  
Test Board ◽  
Silicon Photonic ◽  
Transceiver Module ◽  
Photonic Circuit ◽  
And Performance

Targeting high-speed, low-cost, short-reach intra-datacenter connections, we designed and tested an integrated silicon photonic circuit as a transmitter engine. This engine can be packaged into an optical transceiver module which meets the QSFP-DD Form Factor, together with other electrical/optical components. We first present the design and performance of a high-speed silicon modulator, which had a 3-dB EO bandwidth of >40 GHz and an ER of >5 dB. We then incorporated the engine onto a test board and injected a 53.125 Gbaud PAM4 signal. Clear eye patterns were observed at the receiver with TDECQ ~3 dB for all four lanes.

scholarly journals Spatially Resolved Experimental Modal Analysis on High-Speed Composite Rotors Using a Non-Contact, Non-Rotating Sensor

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4705
Author(s):  
Julian Lich ◽  
Tino Wollmann ◽  
Angelos Filippatos ◽  
Maik Gude ◽  
Juergen Czarske ◽  
...  
Keyword(s):  
High Speed ◽  
Natural Frequencies ◽  
Mode Shapes ◽  
Fiber Reinforced ◽  
Structural Dynamic ◽  
Spatially Resolved ◽  
Glass Fiber Reinforced ◽  
Vibration Responses ◽  
And Performance

Due to their lightweight properties, fiber-reinforced composites are well suited for large and fast rotating structures, such as fan blades in turbomachines. To investigate rotor safety and performance, in situ measurements of the structural dynamic behaviour must be performed during rotating conditions. An approach to measuring spatially resolved vibration responses of a rotating structure with a non-contact, non-rotating sensor is investigated here. The resulting spectra can be assigned to specific locations on the structure and have similar properties to the spectra measured with co-rotating sensors, such as strain gauges. The sampling frequency is increased by performing consecutive measurements with a constant excitation function and varying time delays. The method allows for a paradigm shift to unambiguous identification of natural frequencies and mode shapes with arbitrary rotor shapes and excitation functions without the need for co-rotating sensors. Deflection measurements on a glass fiber-reinforced polymer disk were performed with a diffraction grating-based sensor system at 40 measurement points with an uncertainty below 15 μrad and a commercial triangulation sensor at 200 measurement points at surface speeds up to 300 m/s. A rotation-induced increase of two natural frequencies was measured, and their mode shapes were derived at the corresponding rotational speeds. A strain gauge was used for validation.

Image-Based Versus Signal-Based Sensors for Machine Fault Detection and Isolation

2014 ◽  
Author(s):  
Heshan Fernando ◽  
Vedang Chauhan ◽  
Brian Surgenor
Keyword(s):  
Fault Detection ◽  
High Speed ◽  
Fault Isolation ◽  
Video Data ◽  
Fault Detection And Isolation ◽  
Single Camera ◽  
Multiple Faults ◽  
Multiple Sensors ◽  
Machine Fault ◽  
And Performance

This paper presents the results of a comparative study that investigated the use of image-based and signal-based sensors for fault detection and fault isolation of visually-cued faults on an automated assembly machine. The machine assembles 8 mm circular parts, from a bulk-supply, onto continuously moving carriers at a rate of over 100 assemblies per minute. Common faults on the machine include part jams and ejected parts that occur at different locations on the machine. Two sensor systems are installed on the machine for detecting and isolating these faults: an image-based system consisting of a single camera and a signal-based sensor system consisting of multiple greyscale sensors and limit switches. The requirements and performance of both systems are compared for detecting six faults on the assembly machine. It is found that both methods are able to effectively detect the faults but they differ greatly in terms of cost, ease of implementation, detection time and fault isolation capability. The conventional signal-based sensors are low in cost, simple to implement and require little computing power, but the installation is intrusive to the machine and readings from multiple sensors are required for faster fault detection and isolation. The more sophisticated image-based system requires an expensive, high-resolution, high-speed camera and significantly more processing power to detect the same faults; however, the system is not intrusive to the machine, fault isolation becomes a simpler problem with video data, and the single camera is able to detect multiple faults in its field of view.

The Design and Implementation of ECC High-Speed Encryption Engine Based on FPGA

2012 ◽  
Vol 459 ◽  
pp. 544-548 ◽  
Author(s):  
Wei Liang ◽  
Jian Bo Xu ◽  
Wei Hong Huang ◽  
Li Peng
Keyword(s):  
Data Transmission ◽  
High Speed ◽  
Lower Cost ◽  
Low Cost ◽  
Rapid Development ◽  
Security Technology ◽  
Multiplication Algorithm ◽  
Secure Data Transmission ◽  
And Performance ◽  
Computation Speed

Network security technology ensures secure data transmission in network. Meanwhile, it brings extra overhead of security system in terms of cost and performance, which seriously affects the rapid development of existing high-speed encryption systems. The existing encryption technology cannot meet the demand of high security, low cost and high real-time. For solving above problems, an ECC encryption engine architecture based on scalable public key cipher and a high-speed configurable multiplication algorithm are designed. The algorithm was tested on FPGA platform and the experiment results show that the system has better computation speed and lower cost overhead. By comparing with other systems, our system has benefits in terms of hardware overhead and encryption time ratio

Abstract 371: Down Regulation of ECM Genes Laminin and Collagen IV Lead to Preserved Cardiac Function With Age and Increased Lifespan in Drosophila

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Ayla O Sessions
Keyword(s):  
Diastolic Dysfunction ◽  
High Speed ◽  
Current Model ◽  
Collagen Iv ◽  
Model Systems ◽  
Model Organisms ◽  
Heart Tube ◽  
Ecm Remodeling ◽  
Intercalated Discs ◽  
And Performance

Increased deposition of extracellular matrix (ECM) is observed in all advanced age heart failure patients, but current model systems are complex and slow to age. To investigate the effect of extracellular remodeling on mechanical function in genetically tractable, rapidly aging, and simple model organisms, we employed Drosophila melanogaster, which has a simple trilayered heart tube. We found that two common wildtype strains of Drosophila, i.e. yellow-white (yw) and white-1118 (w1118), exhibit different cytoskeletal and ECM remodeling with age. Using a recently developed nanoindentation method to measure cardiomyocyte stiffness and high speed optical imaging to assess contractility of intact Drosophila hearts, we found that yw flies had stiffer intercalated discs (ICD) and exhibited diastolic dysfunction with age. On the other hand, w1118 flies had a shorter lifespan compared to yw, did not exhibit ICD stiffening, had a less severe diastolic dysfunction, and showed an increase in ECM layer thickness between ventral muscle (VM) and cardiomyocyte (CM) layers of the heart tube. To modulate ECM and assess its effect in the aged w1118 flies, we knocked-down ECM genes LamininA and Viking (homologous to Collagen IV). Both ECM KD genotypes exhibited diastolic dilation with increased fractional shortening at adult (1wk) and aged (5wk) time points. The LamininA KD resulted in decreased cardiomyocyte stiffness correlating with increased relaxation velocities in adult flies and preservation of shortening and relaxation velocities in aged flies over controls. However, both the LamininA and Collagen IV KD flies experienced a basal increase in the decoupling of their cardiomyocytes as determined by heart period variance and % fibrillar heart-beats. These conductance issues were not enough to counteract the increased cardiac output and performance with age, and the Collagen IV KD outlived controls by 1.5 weeks median survival and the LamininA KD by 3 weeks. This suggests that the cell-ECM contacts in the basement membrane are intimately tied not only to the coupling of the cardiomyocytes of the Drosophila heart tube but also to cytoskeletal remodeling, but perhaps different ECM proteins have different mechanisms for interacting with the cardiomyocyte cytoskeleton.

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