scholarly journals Color-Adjustable Devices Based on the Surface Plasmons Effect

2020 ◽  
Vol 10 (6) ◽  
pp. 1960 ◽  
Author(s):  
Kui Wen ◽  
Xinpeng Jiang ◽  
Jie He ◽  
Guofeng Li ◽  
Junbo Yang
Keyword(s):  
Surface Plasmons ◽  
Optical Response ◽  
Dielectric Materials ◽  
Transmission Peak ◽  
Great Promise ◽  
Refractive Indices ◽  
Physical Mechanisms

The optical response of a metamaterial can be engineered by manipulating the size, pattern, and composition of its cells. Here, we present a coloring device, which increases resolution while retaining adjustability. By adding different nanoparticles in the nanohole, the shift of the transmission peak in the visible regions is realizable and manageable, which means a series of different colors are revealed in this device. At the same time, it is also possible to fill the holes with dielectric materials of different refractive indices to achieve the purpose of color diversity. This method theoretically confirms the feasibility of designing a coloring device via surface plasmons-based metamaterial nanostructure, which holds great promise for future versatile utilization of multiple physical mechanisms to render multiple colors in a simple nanostructure.

scholarly journals Graphene Platelets-Based Magnetoactive Materials with Tunable Magnetoelectric and Magnetodielectric Properties

Nanomaterials ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1783
Author(s):  
Ioan Bica ◽  
Eugen Mircea Anitas
Keyword(s):  
Magnetic Field ◽  
Silicone Oil ◽  
Dielectric Materials ◽  
Cotton Fibers ◽  
Magnetic Flux Density ◽  
Electrical Capacitance ◽  
Medium Frequency ◽  
Physical Mechanisms ◽  
Electrical Devices ◽  
Living Organisms

We fabricate hybrid magnetoactive materials (hMAMs) based on cotton fibers, silicone oil, carbonyl iron and graphene nanoplatelets (nGr) at various mass concentrations ΦnGr. The obtained materials are used as dielectric materials for manufacturing plane electrical capacitors. The equivalent electrical capacitance Cp and resistance Rp are measured in an electric field of medium frequency f, without and respectively with a magnetic field of magnetic flux density B in the range from 0.1 T up to 0.5 T. The results are used to extract the components ϵr′ and ϵr″ of the complex relative permittivity ϵr*, and to reveal the magnitude of the induced magnetoelectric couplings kx and magnetodielectric effects MDE. It is shown that ϵr′, ϵr″, kx and MDE are significantly influenced by f,B and ΦnGr. We describe the underlying physical mechanisms in the framework of dipolar approximation and using elements of dielectric theory. The tunable magnetoelectric and magnetodielectric properties of hMAMs are useful for manufacturing electrical devices for electromagnetic shielding of living organisms.

Selection guidelines for ionic dielectrics with gigantic dielectric response (GDR) based on polaronic phase transition criteria

2013 ◽  
Vol 1535 ◽  
Author(s):  
Valeri Ligatchev ◽  
Zhigen Yu ◽  
Jianwei Zheng ◽  
Michael B. Sullivan
Keyword(s):  
Phase Transition ◽  
Dielectric Response ◽  
Physical Nature ◽  
Dielectric Materials ◽  
Physical Mechanisms ◽  
Transition Criteria ◽  
Temperature Ranges ◽  
Experimental And Theoretical Studies ◽  
Very High ◽  
Selection Of

ABSTRACTDielectric materials with GDR (e.g. CaCu3Ti4O12 – CCTO and isostructural systems, co-doped NiO etc) attract major research interest due to their bright prospective in energy storage and memory devices. However, after years of intensive experimental and theoretical studies of GDR materials, physical nature of their extremely high complex dielectric permittivity (specifically, real part ∼ 104 - 106) is still not established convincingly. Another serious problem is excessively high imaginary part of the permittivity (which usually exceeds real one). Better understanding on physical mechanisms and limitations of GDR behavior in aforementioned dielectrics could be achieved based on polaronic phase transition criteria, proposed S. Fratini and P. Quémerais [Eur. Phys. Journ. B14, 99 (2000)]. In particular, ‘melting’ of Polaronic Wigner Crystal (PWC) either to ‘polaronic liquid’ or ‘electron liquid’ manifests two different scenarios of PWC phase transition at increment of concentrations of appropriate dopants. The former scenario is certainly preferable for ionic dielectrics with GDR behavior, while the latter one would yield in metal-like dielectric response with very high real permittivity, but unacceptable loss. Described approach provides physically transparent guidelines for selection of prospective host dielectrics with GDR behavior and quantitative estimations on critical dopant/polaron concentrations, corresponding to both aforementioned types of the phase transitions as well as temperature ranges suitable for GDR.

Diamond Sensors and Vacuummicroelectronics

1995 ◽  
Vol 416 ◽  
Author(s):  
L. S. Pan
Keyword(s):  
High Energy Physics ◽  
High Energy ◽  
Great Promise ◽  
Physical Mechanisms ◽  
Silicon Devices ◽  
Vacuum Microelectronics ◽  
Diamondlike Carbon ◽  
Radiation Sensors ◽  
Physics Experiments ◽  
Energy Physics

ABSTRACTThis paper will cover two diverse electronic applications for which diamond devices have shown great promise. The first application is diamond radiation sensors for high radiation environments, where the competition is mainly silicon devices. These environments arise in high energy physics experiments, and tests show diamond to be superior to silicon in many ways. The second application is vacuum microelectronics, which generally refers to field emission, where the main competitor is metal and semiconductor microtip arrays. Certain diamond and diamondlike carbon materials emit electrons readily, but the physical mechanisms for this are not well understood. Negative electron affinity and other possible explanations are discussed in this paper.

scholarly journals Installation for studying the parameters of localiInstallation for studying the parameters of localization of an electromagnetic wave in a waveguide of variable cross-section in the framework of the predictions of the 5-D extended space modelzation of an electromagnetic wave in a waveguide of variable cross-section in the framework of the predictions of the 5-D extended space model

2021 ◽  
Vol 13 (4) ◽  
pp. 407-418
Author(s):  
Dmitry Yu. Tsipenyuk ◽  
◽  
Sergey I. Derzhavin ◽  
Yaroslav V. Kravchenko ◽  
◽  
...  
Keyword(s):  
Electromagnetic Wave ◽  
Microwave Radiation ◽  
Cross Section ◽  
Variable Mass ◽  
Dielectric Materials ◽  
Variable Cross Section ◽  
Refractive Indices ◽  
Variable Cross ◽  
Space Model ◽  
Extended Space

The paper describes the creation and testing of an experimental setup for studying the parameters of localization of electromagnetic microwave radiation with a power of 0.001-0.004 W in the range of 36.0-79.0 GHz when propagating radiation in metal waveguides of variable cross-section. Measurements will also be carried out under conditions of filling the waveguide with dielectric materials with refractive indices from 1.46 to 4.0 for microwave radiation of the specified range. The installation is designed to measure the parameters of the localization of microwave radiation when it passes through a waveguide of variable cross-section, filled with materials with different refractive indices. Interpretation of the results will be carried out within the framework of the 5-D extended space model (ESM). The extended space model is formulated in (1+4)-dimensional space time-coordinate-interval. An additional spatial coordinate in the ESM is the interval. In the conjugate 5-D space, the energy-momentum-mass interval in the ESM corresponds to mass. In the ESM formalism, the question of the appearance of a nonzero variable mass in a photon and its localization under the influence of an external field is studied.

scholarly journals Influence of direct deposition of dielectric materials on the optical response of monolayer WS2

2021 ◽  
Vol 119 (13) ◽  
pp. 133106
Author(s):  
Tinghe Yun ◽  
Matthias Wurdack ◽  
Maciej Pieczarka ◽  
Semonti Bhattacharyya ◽  
Qingdong Ou ◽  
...  
Keyword(s):  
Optical Response ◽  
Dielectric Materials ◽  
Direct Deposition

scholarly journals Design principles for photonic crystals based on plasmonic nanoparticle superlattices

2018 ◽  
Vol 115 (28) ◽  
pp. 7242-7247 ◽  
Author(s):  
Lin Sun ◽  
Haixin Lin ◽  
Kevin L. Kohlstedt ◽  
George C. Schatz ◽  
Chad A. Mirkin
Keyword(s):  
Photonic Crystals ◽  
Periodic Structures ◽  
Structural Parameters ◽  
Dielectric Materials ◽  
Design Principles ◽  
High Refractive Index ◽  
Lattice Parameter ◽  
Refractive Indices ◽  
Plasmonic Nanoparticle ◽  
Nanoparticle Superlattices

Photonic crystals have been widely studied due to their broad technological applications in lasers, sensors, optical telecommunications, and display devices. Typically, photonic crystals are periodic structures of touching dielectric materials with alternating high and low refractive indices, and to date, the variables of interest have focused primarily on crystal symmetry and the refractive indices of the constituent materials, primarily polymers and semiconductors. In contrast, finite difference time domain (FDTD) simulations suggest that plasmonic nanoparticle superlattices with spacer groups offer an alternative route to photonic crystals due to the controllable spacing of the nanoparticles and the high refractive index of the lattices, even far away from the plasmon frequency where losses are low. Herein, the stopband features of 13 Bravais lattices are characterized and compared, resulting in paradigm-shifting design principles for photonic crystals. Based on these design rules, a simple cubic structure with an ∼130-nm lattice parameter is predicted to have a broad photonic stopband, a property confirmed by synthesizing the structure via DNA programmable assembly and characterizing it by reflectance measurements. We show through simulation that a maximum reflectance of more than 0.99 can be achieved in these plasmonic photonic crystals by optimizing the nanoparticle composition and structural parameters.

scholarly journals Rapid Antibiotic Susceptibility Testing on Pathogenic Bacteria in Solid Growth Medium Using a Real-Time and Contactless Planar Microwave Resonator Sensor

2021 ◽  
Author(s):  
Mandeep Chhajer Jain ◽  
Anupama Pillai ◽  
Rakesh Narang ◽  
Mohammad Zarifi
Keyword(s):  
High Throughput ◽  
Antibiotic Susceptibility ◽  
Pathogenic Bacteria ◽  
Susceptibility Testing ◽  
Dielectric Materials ◽  
Great Promise ◽  
Microwave Resonator ◽  
Antibiotic Susceptibility Testing ◽  
Bacterial Strains ◽  
Non Invasive

Abstract Infection diagnosis and antibiotic susceptibility testing (AST) are pertinent clinical microbiology practices that are in dire need of improvement, as current standards are not able to keep up with the mutations and resistance development of certain bacterial strains. This paper presents a novel way to conduct AST which hybridizes disk diffusion AST with microwave resonators for rapid, contactless, non-invasive and high-throughput testing. This work uses Escherichia coli (E. coli) cultured on solid agar and places bacteria samples on a microwave split-ring resonator along with antibiotic disks (erythromycin) of various doses to demonstrate the viability of this sensing method in a clinical microbiological setting. The microwave resonator, operating at a 1.76 GHz resonant frequency, boasted a 5 mm2 sensitive sensing region. A one-port sensor was designed and optimized for detecting dielectric property variations of lossy dielectric materials accurately. This sensor was calibrated to detect uninhibited growth of the bacteria at 0.005 dB/hr, with a maximum change of 0.07 dB over the course of 15 hrs. The transient resonant amplitude change was subsequently dampened for each increasing dosage of antibiotic tested, with 45 µg of erythromycin showing negligible change indicating complete inhibited growth. This AST sensor demonstrated decisive results of antibiotic susceptibility in under 6 hours and shows great promise to further automate the intricate workflow of AST in clinical settings, while providing rapid, sensitive, non-invasive and high-throughput detection capabilities.

The spindle stage: A powerful optical tool

1988 ◽  
Vol 46 ◽  
pp. 52-53
Author(s):  
Mickey E. Gunter ◽  
F. Donald Bloss
Keyword(s):  
Significant Error ◽  
Optical Data ◽  
Refractive Indices ◽  
Axis Of Rotation ◽  
Polarizing Microscope ◽  
Microscope Stage

A single, reasonably homogeneous, nonopaque 30-to-300 μm crystal, mounted on a spindle stage and studied by immersion methods under a polarizing microscope, yields optical data frequently sufficient to identify and characterize a substance unequivocally. The data obtainable include (1) the orientation of the crystal's principal vibration axes and (2) its principal refractive indices, to within 0.0002 if desired, for light vibrating along these principal vibration axes. Spindle stages tend to be simple and relatively inexpensive, some costing less than $50. They permit rotation of the crystal about a single axis which is parallel to the microscope stage. This spindle or S-axis is thus perpendicular to the M-axis, namely the microscope stage's axis of rotation.A spindle stage excels when studying anisotropic crystals. It orients uniaxial crystals within minutes and biaxial crystals almost as quickly so that their principal refractive indices - ɛ and ω (uniaxial); α, β and γ (biaxial) - can be determined without significant error from crystal misorientation.

Sign in / Sign up

Export Citation Format

Share Document