scholarly journals Fano-Resonance in Hybrid Metal-Graphene Metamaterial and Its Application as Mid-Infrared Plasmonic Sensor

Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 268 ◽  
Author(s):  
Jianfa Zhang ◽  
Qilin Hong ◽  
Jinglan Zou ◽  
Yuwen He ◽  
Xiaodong Yuan ◽  
...  
Keyword(s):  
Fano Resonance ◽  
High Performance ◽  
Figure Of Merit ◽  
Plasmonic Sensor ◽  
Resonance Strength ◽  
Mid Infrared ◽  
Graphene Layers ◽  
The Past ◽  
Potential Applications ◽  
Hybrid Metamaterial

Fano resonances in nanostructures have attracted widespread research interests in the past few years for their potential applications in sensing, switching and nonlinear optics. In this paper, a mid-infrared Fano resonance in a hybrid metal-graphene metamaterial is studied. The hybrid metamaterial consists of a metallic grid enclosing with graphene nanodisks. The Fano resonance arises from the coupling of graphene and metallic plasmonic resonances and it is sharper than plasmonic resonances in pure graphene nanostructures. The resonance strength can be enhanced by increasing the number of graphene layers. The proposed metamaterial can be employed as a high-performance mid-infrared plasmonic sensor with an unprecedented sensitivity of about 7.93 μm/RIU and figure of merit (FOM) of about 158.7.

scholarly journals High Sensitivity Plasmonic Sensor Based on Fano Resonance with Inverted U-Shaped Resonator

Sensors ◽  
2021 ◽  
Vol 21 (4) ◽  
pp. 1164
Author(s):  
Gongli Xiao ◽  
Yanping Xu ◽  
Hongyan Yang ◽  
Zetao Ou ◽  
Jianyun Chen ◽  
...  
Keyword(s):  
Fano Resonance ◽  
Figure Of Merit ◽  
High Sensitivity ◽  
Refractive Index Sensor ◽  
Multimode Interference ◽  
Geometrical Parameters ◽  
The Finite Element Method ◽  
Plasmonic Sensor ◽  
Coupled Mode ◽  
Plasmonic Nanosensor

Herein, we propose a tunable plasmonic sensor with Fano resonators in an inverted U-shaped resonator. By manipulating the sharp asymmetric Fano resonance peaks, a high-sensitivity refractive index sensor can be realized. Using the multimode interference coupled-mode theory and the finite element method, we numerically simulate the influences of geometrical parameters on the plasmonic sensor. Optimizing the structure parameters, we can achieve a high plasmonic sensor with the maximum sensitivity for 840 nm/RIUand figure of merit for 3.9 × 105. The research results provide a reliable theoretical basis for designing high sensitivity to the next generation plasmonic nanosensor.

Preparation of high-performance PEEK anti-wear blends with melt-processable PTFE

2019 ◽  
Vol 32 (6) ◽  
pp. 645-654
Author(s):  
Xiaotao Qiu ◽  
Congli Fu ◽  
Aiqun Gu ◽  
Yang Gao ◽  
Xiuli Wang ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Wear Resistance ◽  
Surface Analysis ◽  
Tribological Properties ◽  
High Performance ◽  
Tribological Performance ◽  
Mechanical And Tribological Properties ◽  
The Past ◽  
Wide Range ◽  
Potential Applications

High-performance anti-wear polyetheretherketone/polytetrafluoroethylene (PEEK/PTFE) blends have drawn much attention over the past few years, owing to their wide range of potential applications. However, a convenient and effective method to prepare such blends with superior mechanical and tribological properties is still lacking. In this work, we propose a promising approach that uses melt-processable PTFE (MP PTFE), instead of conventional PTFE, to prepare anti-wear blends. MP PTFE, with melt flow abilities under appropriate conditions, can disperse homogeneously in PEEK, enhancing both the mechanical and tribological properties of the PEEK/PTFE blend. To prove this postulation, in this work, both MP PTFE and commercial PTFE were blended with PEEK, separately, and the effects of PTFE type and content on the tensile and tribological properties of the blends were studied. The results showed that, although the addition of commercial PTFE to PEEK could increase the wear resistance, it decreased the tensile strength of PEEK significantly. Compared to the blends with commercial PTFE, the blends with MP PTFE exhibited better tribological performance and higher tensile strength for PTFE content below 10 wt%. It was confirmed that the better dispersion of MP PTFE in PEEK endowed the blends with higher tensile strength. The surface analysis indicated that the MP PTFE could readily migrate to and enrich the surfaces of the blends. The relatively high PTFE content on the surface favored the formation of tribo-films, enhancing the tribological properties of the blends.

scholarly journals On The Application of SiO2/SiC Grating on Ag for High-Performance Fiber Optic Plasmonic Sensing of Cortisol Concentration

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1623 ◽  
Author(s):  
Ankit Kumar Pandey ◽  
Anuj K. Sharma ◽  
Carlos Marques
Keyword(s):  
High Performance ◽  
Figure Of Merit ◽  
Fiber Optic ◽  
Limit Of Detection ◽  
Cortisol Concentration ◽  
Practical Implementation ◽  
Angle Of Incidence ◽  
Plasmonic Sensor ◽  
High Performance Fiber ◽  
Better Than

This paper reports on high-accuracy simulation of a grating structure based fiber optic plasmonic sensor for salivary cortisol sensing. Gratings of SiO2 and SiC (one at a time) in combination with a thin Ag layer are considered to be in direct contact with analyte medium (solutions containing different concentrations of cortisol) considering that the groove regions are also filled with analyte. The optimization of Ag layer thickness is carried out to achieve maximum power loss (PL) corresponding to cortisol concentration variation. The variation of PL (in dB) spectra with the angle of incidence (α) is the sensing mechanism of the proposed scheme. Sensing performance is extensively analyzed in terms of sensitivity, limit-of-detection (LOD) and figure-of-merit (FOM) that incorporates both the sensitivity and the width of the corresponding PL curves. While the sensitivity and FOM values are significantly large, the results also reveal that in angular interrogation mode (AIM), an average LOD of 9.9 pg/mL and 9.8 pg/mL is obtained for SiO2 and SiC-based sensor designs, respectively. When the intensity interrogation method (IIM) in place of AIM is considered, an average LOD of 22.6 fg/mL and 68.17 fg/mL is obtained for SiO2 and SiC-based sensor designs, respectively. LOD (with IIM, in particular) is considerably better than the present-state-of-art related to cortisol monitoring. Pragmatic model for possible practical implementation of sensor scheme is also discussed. The involvement of optical fiber in the proposed sensor design makes it possible to implement it as a flexible sensor or for wearable solution for cortisol detection via sweat monitoring as well as for measuring cortisol level in aquaculture tanks where concentration levels are much lower than 10 ng/mL.

scholarly journals Characterization of Exopolysaccharides Produced by Rhizobia Species

2015 ◽  
Vol 39 (6) ◽  
pp. 1566-1575 ◽  
Author(s):  
Tereza Cristina Luque Castellane ◽  
Alda Maria Machado Bueno Otoboni ◽  
Eliana Gertrudes de Macedo Lemos
Keyword(s):  
High Performance ◽  
Biological Properties ◽  
Reversed Phase ◽  
The Past ◽  
Structure And Dynamics ◽  
Key Factor ◽  
Reactive Groups ◽  
Potential Applications ◽  
Species Specific

ABSTRACT Increasing attention has been given, over the past decades, to the production of exopolysaccharides (EPS) from rhizobia, due to their various biotechnological applications. Overall characterization of biopolymers involves evaluation of their chemical, physical, and biological properties; this evaluation is a key factor in understanding their behavior in different environments, which enables researchers to foresee their potential applications. Our focus was to study the EPS produced by Mesorhizobium huakuii LMG14107, M. loti LMG6125, M. plurifarium LMG11892,Rhizobium giardini bv. giardiniH152T, R. mongolense LMG19141, andSinorhizobium (= Ensifer)kostiense LMG19227 in a RDM medium with glycerol as a carbon source. These biopolymers were isolated and characterized by reversed-phase high-performance liquid chromatography (RP-HPLC), Fourier transform infrared (FTIR), and nuclear magnetic resonance (NMR) spectroscopies. Maximum exopolysaccharide production was 3.10, 2.72, and 2.50 g L-1for the strains LMG6125, LMG19227, and LMG19141, respectively. The purified EPS revealed prominent functional reactive groups, such as hydroxyl and carboxylic, which correspond to a typical heteropolysaccharide. The EPS are composed primarily of galactose and glucose. Minor components found were rhamnose, glucuronic acid, and galacturonic acid. Indeed, from the results of techniques applied in this study, it can be noted that the EPS are species-specific heteropolysaccharide polymers composed of common sugars that are substituted by non-carbohydrate moieties. In addition, analysis of these results indicates that rhizobial EPS can be classified into five groups based on ester type, as determined from the 13C NMR spectra. Knowledge of the EPS composition now facilitates further investigations relating polysaccharide structure and dynamics to rheological properties.

scholarly journals Mid-infrared supercontinuum generation in chalcogenide glass fibers: a brief review

PhotoniX ◽  
2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Yingying Wang ◽  
Shixun Dai
Keyword(s):  
Recent Progress ◽  
Glass Fibers ◽  
Optical Nonlinearity ◽  
Mid Infrared ◽  
Silica Glasses ◽  
The Past ◽  
Great Progress ◽  
Potential Applications ◽  
Soft Glasses ◽  
Made In

AbstractChalcogenide (ChG) glasses have the characteristics of a wide transparency window (over 20 μm) and high optical nonlinearity (up to 103 times greater than that of silica glasses), exhibiting great advantages over silica and other soft glasses in optical property at mid-infrared (MIR) wavelength range. These make them excellent candidates for MIR supercontinuum (SC) generation. Over the past decades, great progress has been made in MIR SC generation based on ChG fibers in terms of spectral extension and output power improvement. In this paper, we introduce briefly the properties of ChG glasses and fibers including transmission, nonlinearity, and dispersion, etc. Recent progress in MIR SC generation based on ChG fibers is reviewed from the perspective of pump schemes. We also present novel ChG fibers such as As-free, Te-based, and chalcohalide fibers, which have been explored and employed as nonlinear fibers to achieve broadband SC generation. Moreover, the potential applications of MIR SC sources based on ChG fibers are discussed.

scholarly journals Dual-Band Plasmonic Perfect Absorber Based on Graphene Metamaterials for Refractive Index Sensing Application

Micromachines ◽  
2019 ◽  
Vol 10 (7) ◽  
pp. 443 ◽  
Author(s):  
Zao Yi ◽  
Cuiping Liang ◽  
Xifang Chen ◽  
Zigang Zhou ◽  
Yongjian Tang ◽  
...  
Keyword(s):  
Refractive Index ◽  
Figure Of Merit ◽  
Medical Diagnostics ◽  
Dual Band ◽  
Perfect Absorber ◽  
Plasmonic Sensor ◽  
Refractive Index Sensing ◽  
Potential Applications ◽  
Maximal Absorption ◽  
Sensing Application

We demonstrate a dual-band plasmonic perfect absorber (PA) based on graphene metamaterials. Two absorption peaks (22.5 μm and 74.5 μm) with the maximal absorption of 99.4% and 99.9% have been achieved, respectively. We utilize this perfect absorber as a plasmonic sensor for refractive index (RI) sensing. It has the figure of merit (FOM) of 10.8 and 3.2, and sensitivities of about 5.6 and 17.2 μm/RIU, respectively. Hence, the designed dual-band PA-based RI sensor exhibits good sensing performance in the infrared regime, which offers great potential applications in various biomedical, tunable spectral detecting, environmental monitoring and medical diagnostics.

scholarly journals A flexible micro-thermoelectric device from carbon nanotube-epitaxially grown (Bi,Sb)2Te3 nanocrystal

2021 ◽  
Author(s):  
Qun Jin ◽  
Yang Zhao ◽  
Xuehao Long ◽  
Song Jiang ◽  
Ziqiang Wang ◽  
...  
Keyword(s):  
Thermal Management ◽  
High Performance ◽  
Figure Of Merit ◽  
Open Circuit ◽  
Single Wall Carbon Nanotubes ◽  
Thermoelectric Device ◽  
Potential Applications ◽  
Flexible Thermoelectric ◽  
Growth Approach ◽  
Average Figure

Abstract Flexible thermoelectric (TE) materials have attracted increasing interest due to their potential applications in energy harvesting and high-spatial-resolution thermal management. However, a high-performance flexible micro-TE device (TED) compatible with the modern electronics fabrication process has not yet been developed. Here we report a general van der Waals epitaxial growth approach to fabricating a freestanding and flexible hybrid comprised of single-wall carbon nanotubes and highly ordered (Bi,Sb)2Te3 nanocrystals. High power factors ranging from ~1,680 to ~1,020 µW m−1 K−2 in the temperature range of 300-480 K, combined with a strongly depressed thermal conductivity yield an average figure of merit of ~0.81. A prototype flexible micro-TED module consisting of two p-n hybrids was then fabricated, which demonstrated an unprecedented open circuit voltage of ~22.7 mV and a power density of ~0.36 W cm−2 under a ~30 K temperature difference, and a net cooling temperature of ~22.4 K and a heat absorption density of ~92.5 W cm−2.

scholarly journals Nanoengineered chiral Pt-Ir alloys for high-performance enantioselective electrosynthesis

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Sopon Butcha ◽  
Sunpet Assavapanumat ◽  
Somlak Ittisanronnachai ◽  
Veronique Lapeyre ◽  
Chularat Wattanakit ◽  
...  
Keyword(s):  
High Performance ◽  
Electrochemical Stability ◽  
Lyotropic Liquid Crystal ◽  
Crucial Importance ◽  
Chiral Compound ◽  
Enantiomerically Pure ◽  
Chiral Compounds ◽  
The Past ◽  
Pure Compounds ◽  
Potential Applications

AbstractThe design of efficient chiral catalysts is of crucial importance since it allows generating enantiomerically pure compounds. Tremendous efforts have been made over the past decades regarding the development of materials with enantioselective properties for various potential applications ranging from sensing to catalysis and separation. Recently, chiral features have been generated in mesoporous metals. Although these monometallic matrices show interesting enantioselectivity, they suffer from rather low stability, constituting an important roadblock for applications. Here, a straightforward strategy to circumvent this limitation by using nanostructured platinum-iridium alloys is presented. These materials can be successfully encoded with chiral information by co-electrodeposition from Pt and Ir salts in the simultaneous presence of a chiral compound and a lyotropic liquid crystal as asymmetric template and mesoporogen, respectively. The alloys enable a remarkable discrimination between chiral compounds and greatly improved enantioselectivity when used for asymmetric electrosynthesis (>95 %ee), combined with high electrochemical stability.

scholarly journals Multipolar Plasmonic Resonances of Aluminum Nanoantenna Tuned by Graphene

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 185
Author(s):  
Zhendong Yan ◽  
Qi Zhu ◽  
Xue Lu ◽  
Wei Du ◽  
Xingting Pu ◽  
...  
Keyword(s):  
Electric Fields ◽  
Figure Of Merit ◽  
Near Field ◽  
Monolayer Graphene ◽  
Q Factor ◽  
Order Mode ◽  
Third Order ◽  
Resonance Strength ◽  
Refractive Index Sensing ◽  
Potential Applications

We numerically investigate the multipolar plasmonic resonances of Aluminum nanoantenna tuned by a monolayer graphene from ultraviolet (UV) to visible regime. It is shown that the absorbance of the plasmonic odd modes (l = 1 and l = 3) of graphene–Al nanoribbon structure is enhanced while the absorption at the plasmonic even modes (l = 2) is suppressed, compared to the pure Al nanoribbon structure. With the presence of the monolayer graphene, a change in the resonance strength of the multipolar plasmonic modes results from the near field interactions of the monolayer graphene with the electric fields of the multipolar plasmonic resonances of the Al resonator. In particular, a clear absorption peak with a high quality (Q)-factor of 27 of the plasmonic third-order mode (l = 3) is realized in the graphene–Al nanoribbon structure. The sensitivity and figure of merit of the plasmonic third-order mode of the proposed Graphene–Al nanoribbon structure can reach 25 nm/RIU and 3, respectively, providing potential applications in optical refractive-index sensing.

Sign in / Sign up

Export Citation Format

Share Document