scholarly journals High-Efficiency All-Dielectric Metasurfaces for the Generation and Detection of Focused Optical Vortex for the Ultraviolet Domain

2020 ◽  
Vol 10 (16) ◽  
pp. 5716
Author(s):  
Ziheng Zhang ◽  
Tong Li ◽  
Xiaofei Jiao ◽  
Guofeng Song ◽  
Yun Xu
Keyword(s):  
High Performance ◽  
High Efficiency ◽  
Dielectric Material ◽  
Optical Vortex ◽  
Magnetic Dipoles ◽  
Half Wave ◽  
Potential Applications ◽  
On Chip ◽  
High Flexibility ◽  
Meta Atom

The optical vortex (OV) has drawn considerable attention owing to its tremendous advanced applications, such as optical communication, quantum entanglement, and on-chip detectors. However, traditional OV generators suffer from a bulky configuration and limited performance, especially in the ultraviolet range. In this paper, we utilize a large bandgap dielectric material, niobium pentoxide (Nb2O5), to construct ultra-thin and compact transmission-type metasurfaces to generate and detect the OV at a wavelength of 355 nm. The meta-atom, which operates as a miniature half-wave plate and demonstrates a large tolerance to fabrication error, manipulates the phase of an incident right-handed circular polarized wave with high cross-polarized conversion efficiency (around 86.9%). The phase delay of π between the orthogonal electric field component is attributed to the anti-parallel magnetic dipoles induced in the nanobar. Besides, focused vortex generation (topological charge l from 1 to 3) and multichannel detection (l from −2 to 2) are demonstrated with high efficiency, up to 79.2%. We envision that our devices of high flexibility may have potential applications in high-performance micron-scale integrated ultraviolet nanophotonics and meta-optics.

scholarly journals Solution-Processed Transparent Conducting Electrodes for Flexible Organic Solar Cells with 16.61% Efficiency

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Juanyong Wan ◽  
Yonggao Xia ◽  
Junfeng Fang ◽  
Zhiguo Zhang ◽  
Bingang Xu ◽  
...  
Keyword(s):  
Solar Cells ◽  
Work Function ◽  
Organic Solar Cells ◽  
High Performance ◽  
High Efficiency ◽  
Electrical Stability ◽  
Solution Processed ◽  
Good Thermal Stability ◽  
Transparent Conducting ◽  
High Flexibility

AbstractNonfullerene organic solar cells (OSCs) have achieved breakthrough with pushing the efficiency exceeding 17%. While this shed light on OSC commercialization, high-performance flexible OSCs should be pursued through solution manufacturing. Herein, we report a solution-processed flexible OSC based on a transparent conducting PEDOT:PSS anode doped with trifluoromethanesulfonic acid (CF3SO3H). Through a low-concentration and low-temperature CF3SO3H doping, the conducting polymer anodes exhibited a main sheet resistance of 35 Ω sq−1 (minimum value: 32 Ω sq−1), a raised work function (≈ 5.0 eV), a superior wettability, and a high electrical stability. The high work function minimized the energy level mismatch among the anodes, hole-transporting layers and electron-donors of the active layers, thereby leading to an enhanced carrier extraction. The solution-processed flexible OSCs yielded a record-high efficiency of 16.41% (maximum value: 16.61%). Besides, the flexible OSCs afforded the 1000 cyclic bending tests at the radius of 1.5 mm and the long-time thermal treatments at 85 °C, demonstrating a high flexibility and a good thermal stability.

scholarly journals Phyllotaxis-inspired nanosieves with multiplexed orbital angular momentum

eLight ◽  
2021 ◽  
Vol 1 (1) ◽  
Author(s):  
Zhongwei Jin ◽  
David Janoschka ◽  
Junhong Deng ◽  
Lin Ge ◽  
Pascal Dreher ◽  
...  
Keyword(s):  
Free Space ◽  
High Capacity ◽  
Vortex Generator ◽  
Optical Vortex ◽  
Optical Vortices ◽  
Time Resolved ◽  
Optical Applications ◽  
On Chip ◽  
Pine Cones ◽  
Meta Atom

AbstractNanophotonic platforms such as metasurfaces, achieving arbitrary phase profiles within ultrathin thickness, emerge as miniaturized, ultracompact and kaleidoscopic optical vortex generators. However, it is often required to segment or interleave independent sub-array metasurfaces to multiplex optical vortices in a single nano-device, which in turn affects the device’s compactness and channel capacity. Here, inspired by phyllotaxis patterns in pine cones and sunflowers, we theoretically prove and experimentally report that multiple optical vortices can be produced in a single compact phyllotaxis nanosieve, both in free space and on a chip, where one meta-atom may contribute to many vortices simultaneously. The time-resolved dynamics of on-chip interference wavefronts between multiple plasmonic vortices was revealed by ultrafast time-resolved photoemission electron microscopy. Our nature-inspired optical vortex generator would facilitate various vortex-related optical applications, including structured wavefront shaping, free-space and plasmonic vortices, and high-capacity information metaphotonics.

scholarly journals On-Chip Construction of Multilayered Hydrogel Microtubes for Engineered Vascular-Like Microstructures

Micromachines ◽  
2019 ◽  
Vol 10 (12) ◽  
pp. 840 ◽  
Author(s):  
Tao Yue ◽  
Na Liu ◽  
Yuanyuan Liu ◽  
Yan Peng ◽  
Shaorong Xie ◽  
...  
Keyword(s):  
Microfluidic Device ◽  
Efficient Method ◽  
High Efficiency ◽  
Flow Conditions ◽  
Artificial Blood ◽  
Assembly Method ◽  
Artificial Blood Vessels ◽  
Direct Fabrication ◽  
Potential Applications ◽  
On Chip

Multilayered and multicellular structures are indispensable for constructing functional artificial tissues. Engineered vascular-like microstructures with multiple layers are promising structures to be functionalized as artificial blood vessels. In this paper, we present an efficient method to construct multilayer microtubes embedding different microstructures based on direct fabrication and assembly inside a microfluidic device. This four-layer microfluidic device has two separate inlets for fabricating various microstructures. We have achieved alternating-layered microtubes by controlling the fabrication, flow, and assembly time of each microstructure, and as well, double-layered microtubes have been built by a two-step assembly method. Modifications of both the inner and outer layers was successfully demonstrated, and the flow conditions during the on-chip assembly were evaluated and optimized. Each microtube was successfully constructed within several minutes, showing the potential applications of the presented method for building engineered vascular-like microstructures with high efficiency.

scholarly journals Low-Powered Photodetector Based on Two-Dimensional InS0.3Se0.7/WS2 Heterostructure

2021 ◽  
Vol 13 (12) ◽  
pp. 6883
Author(s):  
Kaiting Zhang ◽  
Jie Chang ◽  
Chaoyang Tan ◽  
Hui Han
Keyword(s):  
High Performance ◽  
High Efficiency ◽  
Lattice Mismatch ◽  
Response Speed ◽  
Building Blocks ◽  
Two Dimensional ◽  
Photoelectric Properties ◽  
Two Dimensional Materials ◽  
Potential Applications ◽  
Vdw Heterostructure

Photodetectors based on two-dimensional (2D) materials have great potential applications in the field of new energy, such as fuel cells, solar cells, and other fields. Van der Waals (vdW) heterojunction photodiodes are expected to be one of the promising applications of two-dimensional materials due to the photoelectric properties without consideration of lattice mismatch. High-efficiency photoelectric sensors based on two-dimensional materials have great significance to reducing the energy consumption of devices. Here, we build a complex vdW heterostructure by combining InS0.3Se0.7 with another suitable 2D material WS2. Few-layer graphite was used as electrodes to enhance the optoelectronic performance of indium monochalcogenides. Evident photocurrent is observed in the InS0.3Se0.7/WS2 vdW heterostructure device arising from the formed p–n junction at the interface. The uniformity and photoresponse of the InS0.3Se0.7/WS2 vdW heterostructure has been further investigated by the photocurrent mapping. It shows that the entire photovoltaic current was originated from the InS0.3Se0.7/WS2 vdW heterojunction by scanning photocurrent microscope images. Furthermore, the response speed is enhanced at small bias voltage. The transient photoresponse can be well reproduced in almost 100 cycles, indicating the good repeatable optoelectronic performance. Our study indicates that the as-prepared InS0.3Se0.7/WS2 vdW heterostructures are attractive building blocks for photodetectors application. Our findings will open up a new way to further develop high-performance, low-power, and energy-efficient photodetectors based on indium monochalcogenides.

Aromatic Polyurea for High Temperature High Energy Density Capacitors

2008 ◽  
Vol 1134 ◽  
Author(s):  
Yong Wang ◽  
Xin Zhou ◽  
Minren Lin ◽  
Sheng-Guo David Lu ◽  
Jun-Hong Lin ◽  
...  
Keyword(s):  
High Temperature ◽  
Energy Density ◽  
High Performance ◽  
High Efficiency ◽  
Breakdown Strength ◽  
Dielectric Material ◽  
Weibull Model ◽  
High Energy ◽  
High Energy Density ◽  
Low Dissipation

AbstractWe investigate aromatic polyureas which can be fabricated in the form of thin films through CVD. It was found that the polymer possesses a flat dielectric response (k∼ 4.2 and loss <1%)) to more than 200°C. The frequency-independent dielectric properties in the investigated frequency range(1kHz∼1MHz), low conductance, low dissipation factor (∼0.005), high breakdown strength (>800MV/m), high energy density (>12J/cm3) and high efficiency suggest this polymer can be a good candidate material for high temperature energy storage capacitors. Breakdown strength was analyzed with Weibull model over a broad temperature range (25°C ∼180°C). Experimental results indicate that aromatic polyurea is more like a nonpolar linear dielectric material because of its highly cross-linked structures. The experiment results further show that this polymer maintains its high performance even at high temperatures.

scholarly journals Low-Temperature Induced Enhancement of Photoelectric Performance in Semiconducting Nanomaterials

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1131
Author(s):  
Liyun Wu ◽  
Yun Ji ◽  
Bangsen Ouyang ◽  
Zhengke Li ◽  
Ya Yang
Keyword(s):  
Crystal Structure ◽  
Low Temperature ◽  
High Performance ◽  
High Efficiency ◽  
Extreme Conditions ◽  
Photoelectric Conversion ◽  
Working Mechanism ◽  
Innovative Strategy ◽  
Photoelectric Performance ◽  
Potential Applications

The development of light-electricity conversion in nanomaterials has drawn intensive attention to the topic of achieving high efficiency and environmentally adaptive photoelectric technologies. Besides traditional improving methods, we noted that low-temperature cooling possesses advantages in applicability, stability and nondamaging characteristics. Because of the temperature-related physical properties of nanoscale materials, the working mechanism of cooling originates from intrinsic characteristics, such as crystal structure, carrier motion and carrier or trap density. Here, emerging advances in cooling-enhanced photoelectric performance are reviewed, including aspects of materials, performance and mechanisms. Finally, potential applications and existing issues are also summarized. These investigations on low-temperature cooling unveil it as an innovative strategy to further realize improvement to photoelectric conversion without damaging intrinsic components and foresee high-performance applications in extreme conditions.

scholarly journals High-Efficiency and Wide-Angle Versatile Polarization Controller Based on Metagratings

Materials ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 623 ◽  
Author(s):  
Kun Song ◽  
Ruonan Ji ◽  
Duman Shrestha ◽  
Changlin Ding ◽  
Yahong Liu ◽  
...  
Keyword(s):  
Electromagnetic Waves ◽  
High Performance ◽  
High Efficiency ◽  
Wide Angle ◽  
Polarization Control ◽  
Dielectric Gratings ◽  
Single Function ◽  
Half Wave ◽  
Single Structure ◽  
Quarter Wave

Metamaterials with their customized properties enable us to efficiently manipulate the polarization states of electromagnetic waves with flexible approaches, which is of great significance in various realms. However, most current metamaterial-based polarization controllers can only realize single function, which has extremely hindered the expansion of their applications. Here, we experimentally demonstrate highly efficient and multifunctional polarization conversion effects using metagrating by integrating single-structure metallic meta-atoms into the dielectric gratings. Benefiting from the combined advantages of the gratings and the metamaterials, the considered metagrating can operate in transmission and reflection modes simultaneously, acting as a high-performance and wide-angle quarter-wave or half-wave plate with distinct functions in different frequency bands. This metagrating structure is scalable to other frequency ranges and may provide opportunities to design compact multifunctional optical polarization control devices.

Low half-wave voltage Y-branch electro-optic polymer modulator based on side-chain polyurethane-imide

2016 ◽  
Vol 30 (17) ◽  
pp. 1650228 ◽  
Author(s):  
Jie Tang ◽  
Long-De Wang ◽  
Ruo-Zhou Li ◽  
Qiang Zhang ◽  
Tong Zhang
Keyword(s):  
High Performance ◽  
Low Cost ◽  
Core Layer ◽  
Optical Systems ◽  
Side Chain ◽  
Driving Voltage ◽  
Half Wave Voltage ◽  
Half Wave ◽  
Electro Optic ◽  
Potential Applications

A Y-branch electro-optic (EO) polymer modulator has been designed and fabricated. High performance side-chain polyurethane-imide (PUI) with a high EO coefficient of larger than 50 pm/V and a moderate glass-transition temperature [Formula: see text] of 206[Formula: see text]C is used as EO polymer core layer of the modulator. The fabricated phase modulator exhibits a low half-wave voltage of 1.94 V at 1550 nm in single arm modulation with 1 cm EO interaction length and 2 cm total length. The results show that the modulator fabricated by side-chain PUI EO materials possesses potential applications in low driving voltage and low cost optical systems.

High-Performance Hardware Interpolation Architecture for High Efficiency Video Coding Decoder

2016 ◽  
Vol 11 (9) ◽  
pp. 764
Author(s):  
Lella Aicha Ayadi ◽  
Nihel Neji ◽  
Hassen Loukil ◽  
Mouhamed Ali Ben Ayed ◽  
Nouri Masmoudi
Keyword(s):  
Video Coding ◽  
High Performance ◽  
High Efficiency ◽  
High Efficiency Video Coding

Efficient Instruction and Data Caching for High Performance Embedded Processors

1970 ◽  
pp. 9
Author(s):  
A. Ferrerón Labari ◽  
D. Suárez Gracia ◽  
V. Viñals Yúfera
Keyword(s):  
Embedded Systems ◽  
Power Consumption ◽  
Low Power ◽  
Interconnection Networks ◽  
High Performance ◽  
Critical Issue ◽  
Content Management ◽  
Structure Design ◽  
Portable Devices ◽  
On Chip

In the last years, embedded systems have evolved so that they offer capabilities we could only find before in high performance systems. Portable devices already have multiprocessors on-chip (such as PowerPC 476FP or ARM Cortex A9 MP), usually multi-threaded, and a powerful multi-level cache memory hierarchy on-chip. As most of these systems are battery-powered, the power consumption becomes a critical issue. Achieving high performance and low power consumption is a high complexity challenge where some proposals have been already made. Suarez et al. proposed a new cache hierarchy on-chip, the LP-NUCA (Low Power NUCA), which is able to reduce the access latency taking advantage of NUCA (Non-Uniform Cache Architectures) properties. The key points are decoupling the functionality, and utilizing three specialized networks on-chip. This structure has been proved to be efficient for data hierarchies, achieving a good performance and reducing the energy consumption. On the other hand, instruction caches have different requirements and characteristics than data caches, contradicting the low-power embedded systems requirements, especially in SMT (simultaneous multi-threading) environments. We want to study the benefits of utilizing small tiled caches for the instruction hierarchy, so we propose a new design, ID-LP-NUCAs. Thus, we need to re-evaluate completely our previous design in terms of structure design, interconnection networks (including topologies, flow control and routing), content management (with special interest in hardware/software content allocation policies), and structure sharing. In CMP environments (chip multiprocessors) with parallel workloads, coherence plays an important role, and must be taken into consideration.

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