scholarly journals A TM-Pass/TE-Stop Polarizer Based on a Surface Plasmon Resonance

2011 ◽  
Vol 2011 ◽  
pp. 1-6 ◽  
Author(s):  
Yuu Wakabayashi ◽  
Junji Yamauchi ◽  
Hisamatsu Nakano
Keyword(s):  
Wavelength Range ◽  
Metal Film ◽  
Oblique Incidence ◽  
Extinction Ratio ◽  
Normal Incidence ◽  
Metal Films ◽  
Range Shifts ◽  
Dielectric Gratings ◽  
Dielectric Grating ◽  
Difference Time

A TM-pass/TE-stop polarizer consisting of a metal film sandwiched between dielectric gratings is investigated using the finite-difference time-domain method. At normal incidence with respect to the grating plane, a transmissivity of more than 94% and a reflectivity of more than 98% are obtained at  m for the TM and TE waves, respectively. The extinction ratio is more than 17 dB over a wavelength range of 1.50 m to 1.75 m. A high extinction ratio is maintained at oblique incidence, although the wavelength range shifts towards longer wavelengths. The TM-pass/TE-stop operation is also achieved with a modified structure, in which a dielectric grating is sandwiched between metal films.

scholarly journals Broadband Absorption Based on Thin Refractory Titanium Nitride Patterned Film Metasurface

Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1092
Author(s):  
Dewang Huo ◽  
Xinyan Ma ◽  
Hang Su ◽  
Chao Wang ◽  
Hua Zhao
Keyword(s):  
Titanium Nitride ◽  
Oblique Incidence ◽  
Normal Incidence ◽  
Perfect Absorber ◽  
Size Parameter ◽  
Perfect Absorption ◽  
Broadband Absorption ◽  
Solar Energy Harvesting ◽  
Difference Time ◽  
High Absorption

In this paper, a thin metasurface perfect absorber based on refractory titanium nitride (TiN) is proposed. The size parameter of the metasurface is investigated based on the finite difference time domain method and transfer matrix method. With only a 15-nm-thick TiN layer inside the silica/TiN/silica stacks standing on the TiN substrate, the near-perfect absorption throughout the visible regime is realized. The cross-talk between the upper and lower dielectric layers enables the broadening of the absorption peak. After patterning the thin film into a nanodisk array, the resonances from the nanodisk array emerge to broaden the high absorption bandwidth. As a result, the proposed metasurface achieves perfect absorption in the waveband from 400 to 2000 nm with an average absorption of 95% and polarization-insensitivity under the normal incidence. The proposed metasurface maintains average absorbance of 90% up to 50-degree oblique incidence for unpolarized light. Our work shows promising potential in the application of solar energy harvesting and other applications requiring refractory metasurfaces.

Calculation of the Ion Optical Properties of Inhomogeneous Magnetic Sector Fields Part 3: Oblique Incidence and Exit at Curved Boundaries

1959 ◽  
Vol 14 (9) ◽  
pp. 822-827 ◽  
Author(s):  
H. A. Tasman ◽  
A. J. H. Boerboom ◽  
H. Wachsmuth
Keyword(s):  
Oblique Incidence ◽  
Normal Incidence ◽  
Second Order ◽  
Resolving Power ◽  
High Mass ◽  
Curved Boundaries ◽  
Magnetic Sector ◽  
Mass Resolving Power ◽  
Mass Dispersion ◽  
Fringing Fields

In previous papers 1.2we presented the radial second order imaging properties of inhomogeneous magnetic sector fields with normal incidence and exit at plane boundaries. These fields may provide very high mass resolving power and mass dispersion without increase in radius or decrease of slit widths. In the present paper the calculations are extended to include the effect of oblique incidence and exit at curved boundaries. The influence of the fringing fields on axial focusing when the boundaries are oblique, is accounted for. It is shown that the second order angular aberration may Le eliminated by appropriate curvature of the boundaries.

scholarly journals Tunable Infrared Optical Switch Based on Vanadium Dioxide

Nanomaterials ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2988
Author(s):  
Qi Wang ◽  
Shijie Zhang ◽  
Chen Wang ◽  
Rui Li ◽  
Tianhan Cai ◽  
...  
Keyword(s):  
Thin Film ◽  
Vanadium Dioxide ◽  
Optical Switching ◽  
Modulation Depth ◽  
Optical Switch ◽  
Extinction Ratio ◽  
Infrared Region ◽  
Metallic Phase ◽  
Ultrafast Switching ◽  
Difference Time

A tunable infrared optical switch based on a plasmonic structure consisting of aluminum nanoarrays with a thin film of vanadium dioxide is proposed. This optical switch can realize arbitrary wavelength-selective optical switching in the mid-infrared region by altering the radii of the aluminum nanoarrays. Furthermore, since vanadium dioxide transforms from its low-temperature insulator phase to a high-temperature metallic phase when heated or applied voltage, the optical switch can achieve two-way switching of its “ON” and “OFF” modes. Finite-difference time-domain software is used to simulate the performance of the proposed infrared optical switch. Simulation results show that the switch offers excellent optical performances, that the modulation depth can reach up to 99.4%, and that the extinction ratio exceeds −22.16 dB. In addition, the phase transition time of vanadium dioxide is on the femtosecond scale, which means that this optical switch based on a vanadium dioxide thin film can be used for ultrafast switching.

scholarly journals A New Analytical Expression for the T.C.R. of Thin Monocrystalline Metal Films

1979 ◽  
Vol 5 (4) ◽  
pp. 209-213 ◽  
Author(s):  
C. R. Tellier
Keyword(s):  
Electrical Conductivity ◽  
Relaxation Time ◽  
Reflection Coefficient ◽  
Grain Boundary ◽  
Metal Film ◽  
Approximate Equation ◽  
Metal Films ◽  
Exact Equation ◽  
Temperature Coefficient Of Resistivity ◽  
Comparison Of The Results

The analysis of electrical conductivity of continuous thin monocrystalline metal film has been treated by assuming that the scattering from other sources than grain-boundaries can be described by an effective relaxation time. This relaxation time method is applied to the temperature coefficient of resistivity and leads to an analytical approximate equation in terms of the grain-boundary reflection coefficientrand the reduced thicknessk.Comparison of the results with those deduced from the exact equation (derived from the Mayadas and Shatzkes theory) shows that they deviate by less than 5% in largek–,p–, andr– ranges.

scholarly journals Phenomenon of Electromagnetic Field Resonance in Metal and Dielectric Gratings and Its Possible Practical Applications

2020 ◽  
Vol 5 (3) ◽  
pp. 49
Author(s):  
Stefano Bellucci ◽  
Andrii Bendziak ◽  
Oleksandr Vernyhor ◽  
Volodymyr M. Fitio
Keyword(s):  
Refractive Index ◽  
Buffer Layer ◽  
Propagation Constant ◽  
Refractive Index Change ◽  
Dielectric Substrate ◽  
Angular Sensitivity ◽  
Practical Applications ◽  
Dielectric Gratings ◽  
Constant Change ◽  
Dielectric Grating

Calculations of the field distribution in the structure of the dielectric substrate/buffer layer/volume phase grating/analyzed medium were performed. It is shown that in the presence of a buffer layer with a low refractive index in the dielectric waveguide leads to a shift of the maximum field at the waveguide resonance into analyzed medium. As a result, the spectral and angular sensitivity of the corresponding sensor increases. Based on the waveguide equation, analytical expressions are obtained that connect the spectral and angular sensitivity of the sensor to the sensitivity of the propagation constant change due to the refractive index change of the analyzed medium. The conditions for the excitation of the resonance of surface plasmon–polariton waves in the structure with a metal or dielectric grating on a metal substrate are also given. The fields that occur at resonance for silver and gold gratings are calculated.

Numerical Simulation of Penetration Effect of Spherical Fragment on Square Honeycomb Sandwich Plate

2011 ◽  
Vol 474-476 ◽  
pp. 1869-1873 ◽  
Author(s):  
Tao Wang ◽  
Wen Li Yu ◽  
San Qiang Dong ◽  
Yun Liang Gao
Keyword(s):  
Oblique Incidence ◽  
Sandwich Plate ◽  
Normal Incidence ◽  
Impact Angle ◽  
Damage Effect ◽  
Penetration Effect ◽  
Honeycomb Sandwich ◽  
Honeycomb Sandwich Plate ◽  
Solid Plate ◽  
Active Fragment

In this paper, a spherical fragment penetrating to square honeycomb sandwich plate and solid plate which has the same mass as sandwich plate are simulated by LS-DYNA code. The fragment impacts plates at normal incidence and oblique incidence with 30º impact angle at the velocity of 300m/s, 350m/s, 380m/s, 400m/s, 450m/s and 500m/s separately. And the damage pattern of sandwich plate, the acceleration of fragment and the energy absorption of sandwich plate are acquired. For sandwich plate, the acceleration of fragment is less than that of solid plate and the internal energy absorbed is larger that that of solid plate. The result can be used to design new active fragment to improve the damage effect to sandwich plate.

scholarly journals Reconfigurable honeycomb metamaterial absorber having incident angular stability

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Javad Shabanpour ◽  
Sina Beyraghi ◽  
Homayoon Oraizi
Keyword(s):  
Electromagnetic Interference ◽  
Oblique Incidence ◽  
Mechanical Performance ◽  
Incident Angle ◽  
Normal Incidence ◽  
Metallic Phase ◽  
Metamaterial Absorber ◽  
Angular Stability ◽  
Ohmic Losses ◽  
Potential Applications

Abstract Ultrawide-angle electromagnetic wave absorbers with excellent mechanical properties are required in many diverse applications such as sensing, and stealth technologies. Here, a novel 3D reconfigurable metamaterial absorber (MMA) consisting of honeycomb and VO2 films is proposed. The proposed MMA exhibits a strong absorptivity above 90% in the widest incident angle up to $$87^\circ $$ 87 ∘ for TM- and TE polarized oblique incidences for THz wave propagating in yoz-plane. Under normal incidence, when VO2 films are in the insulating state, the proposed absorber exhibits high absorptivity in the frequency band of 1–4 THz. By increasing the temperature of the whole structure, the structural transformation of VO2 occurs and turns into the metallic phase. We have shown that under oblique incidence, the ohmic losses of VO2 films especially those parallel to the direction of the incident electric field are the most important absorption principles of the proposed MMA. Due to the ultra wide-angle absorption (angular stability) and mechanical performance, it is expected that the presented MMA may find potential applications, such as camouflage technologies, electromagnetic interference, imaging, and sensing. To the best knowledge of authors, the proposed MMA configuration exhibits the absorptivity in the widest incident angle ever reported.

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