scholarly journals Theoretical Investigation of a Simple Design of Triple-Band Terahertz Metamaterial Absorber for High-Q Sensing

2019 ◽  
Vol 9 (7) ◽  
pp. 1410 ◽  
Author(s):  
Tao Chen ◽  
Runyu Zhao ◽  
Ben-Xin Wang
Keyword(s):  
Refractive Index ◽  
Narrow Band ◽  
Metamaterial Absorber ◽  
Resonance Absorption ◽  
Simple Design ◽  
Perfect Absorption ◽  
High Q ◽  
Au Film ◽  
Resonance Modes ◽  
Triple Band

This paper presents a simple metamaterial design to achieve the triple-band near-perfect absorption response that can be used in the area of sensor application. The introduced absorber consists of an array of Au strip and a bulk flat Au film separated by an insulator dielectric layer. Three narrow-band resonance absorption peaks are obtained by superposing three different modes (a fundamental mode resonance and two high-order responses) of the Au strip. These resonance modes (in particular of the last two modes) have large sensitivity to the changes of the surrounding index, overlayer thickness and the refractive index of the overlayer.

scholarly journals Perfect Absorption and Refractive-Index Sensing by Metasurfaces Composed of Cross-Shaped Hole Arrays in Metal Substrate

Nanomaterials ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 63
Author(s):  
Zhendong Yan ◽  
Chaojun Tang ◽  
Guohua Wu ◽  
Yumei Tang ◽  
Ping Gu ◽  
...  
Keyword(s):  
Refractive Index ◽  
High Performance ◽  
Narrow Band ◽  
Label Free ◽  
Hybrid Mode ◽  
Perfect Absorption ◽  
Refractive Index Sensing ◽  
Sensing Applications ◽  
Silver Substrate ◽  
Hole Arrays

Achieving perfect electromagnetic wave absorption with a sub-nanometer bandwidth is challenging, which, however, is desired for high-performance refractive-index sensing. In this work, we theoretically study metasurfaces for sensing applications based on an ultra-narrow band perfect absorption in the infrared region, whose full width at half maximum (FWHM) is only 1.74 nm. The studied metasurfaces are composed of a periodic array of cross-shaped holes in a silver substrate. The ultra-narrow band perfect absorption is related to a hybrid mode, whose physical mechanism is revealed by using a coupling model of two oscillators. The hybrid mode results from the strong coupling between the magnetic resonances in individual cross-shaped holes and the surface plasmon polaritons on the top surface of the silver substrate. Two conventional parameters, sensitivity (S) and figure of merit (FOM), are used to estimate the sensing performance, which are 1317 nm/RIU and 756, respectively. Such high-performance parameters suggest great potential for the application of label-free biosensing.

A single-patterned five-band terahertz metamaterial absorber based on multiple resonance mechanisms

2018 ◽  
Vol 32 (03) ◽  
pp. 1850029 ◽  
Author(s):  
Zong-De Ju ◽  
Guo-Qing Xu ◽  
Zhi-Hua Wei ◽  
Jing Li ◽  
Qian Zhao ◽  
...  
Keyword(s):  
High Performance ◽  
Imaging System ◽  
Metamaterial Absorber ◽  
Polarization Angle ◽  
Absorption Mechanism ◽  
Perfect Absorption ◽  
Simple Method ◽  
Multiple Resonance ◽  
Resonance Modes ◽  
Single Pattern

A single-patterned five-band terahertz metamaterial absorber based on simple metal–dielectric–metal sandwich structure is investigated and demonstrated. The numerical simulations reveal the different dependence of the absorption ability on the incident polarization angle, dielectric layer, and structural dimensions of the single pattern. The extracted electric field distribution indicates that the five-band near-perfect absorption performance (average over 98%) mainly originates from the combination of LC, dipole, quadrupole, and high-order resonance. The researches on magnetic field and power loss density distributions further reveal the absorption mechanism. Moreover, additional resonance mode can be excited to form a six-band high-performance absorber only by adjusting some geometric dimensions of the single pattern with multiple resonance modes. The simple method provides us a very good idea to implement a super multi-band absorber. The proposed absorbers here can be applied in massive related fields, such as metamaterial sensors, thermal radiation, and imaging system.

scholarly journals An Ultra-thin Multiband Terahertz Metamaterial Absorber and Sensing Applications

2021 ◽  
Author(s):  
Jinjun Bai ◽  
Wei Shen ◽  
Shasha Wang ◽  
Meilan Ge ◽  
Tingting Chen ◽  
...  
Keyword(s):  
Refractive Index ◽  
Metamaterial Absorber ◽  
Field Energy ◽  
Absorption Mechanism ◽  
Energy Distributions ◽  
Perfect Absorption ◽  
Sensing Applications ◽  
At Resonance ◽  
Potential Applications ◽  
Electromagnetic Field Energy

Abstract We propose an ultra-thin multiband terahertz metamaterial absorber, whose thickness is only 3.8μm. Simulation results show that we can get four narrow absorption peaks with near-perfect absorption in the 4.5 THz-6.0 Thz frequency range. The resonance absorption mechanism is interpreted by the electromagnetic field energy distributions at resonance frequency. Moreover, we also analyze the sensing performances of the absorber in the refractive index and the thickness of the analyte. The refractive index and thickness sensitivities of the sensor are 0.471THz/RIU, 36.594THz/RIU and the FOMs are 8.887RIU -1 , 938.308RIU -1 , respectively. The absorber has potential applications in photodetector, multi-spectral imaging and biosensors.

scholarly journals A Theoretical Terahertz Metamaterial Absorber Structure with a High Quality Factor Using Two Circular Ring Resonators for Biomedical Sensing

Inventions ◽  
2021 ◽  
Vol 6 (4) ◽  
pp. 78
Author(s):  
Sagnik Banerjee ◽  
Uddipan Nath ◽  
Purba Dutta ◽  
Amitkumar Vidyakant Jha ◽  
Bhargav Appasani ◽  
...  
Keyword(s):  
Refractive Index ◽  
Quality Factor ◽  
Metamaterial Absorber ◽  
Circular Ring ◽  
Ring Resonators ◽  
Radiation Absorption ◽  
Refractive Index Sensor ◽  
Perfect Absorption ◽  
Biomedical Sensing ◽  
Sensing Applications

Metamaterial absorbers, on account of their inherent property of electromagnetic radiation absorption, have become a center of attraction for many researchers in recent times. This paper proposes a unique design of a terahertz metamaterial absorber that can be used to sense biomedical samples. The proposed design consists of two identical circular ring resonators (CRRs) made of aluminum on top of a gallium arsenide (GaAs) substrate. On account of its high field confinement in the sensing regime, a near-to-perfect absorption rate of 99.50% is achieved at a frequency of 2.64 THz, along with a large quality factor (Q-Factor) of 44. The design is highly sensitive to the refractive index changes in the encompassing medium. Hence, the proposed absorber can be used as a refractive index sensor exhibiting a reasonable sensitivity of 1500 GHz/RIU and a figure of merit (FoM) of 25. The refractive index range has been varied in the range of 1.34 to 1.39. As many biomedical samples, including cancerous cells, reside within this range, the proposed sensor can be used for biomedical sensing applications.

scholarly journals A Tunable Triple-Band Near-Infrared Metamaterial Absorber Based on Au Nano-Cuboids Array

Nanomaterials ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 207 ◽  
Author(s):  
Feng Qin ◽  
Zeqiang Chen ◽  
Xifang Chen ◽  
Zao Yi ◽  
Weitang Yao ◽  
...  
Keyword(s):  
Surface Plasmons ◽  
Near Infrared ◽  
Structural Parameters ◽  
Fdtd Method ◽  
Field Enhancement ◽  
Metamaterial Absorber ◽  
Infrared Band ◽  
Perfect Absorption ◽  
Tunable Metamaterial ◽  
Triple Band

In this article, we present a design for a triple-band tunable metamaterial absorber with an Au nano-cuboids array, and undertake numerical research about its optical properties and local electromagnetic field enhancement. The proposed structure is investigated by the finite-difference time domain (FDTD) method, and we find that it has triple-band tunable perfect absorption peaks in the near infrared band (1000–2500 nm). We investigate some of structure parameters that influence the fields of surface plasmons (SP) resonances of the nano array structure. By adjusting the relevant structural parameters, we can accomplish the regulation of the surface plasmons resonance (SPR) peaks. In addition, the triple-band resonant wavelength of the absorber has good operational angle-polarization-tolerance. We believe that the excellent properties of our designed absorber have promising applications in plasma-enhanced photovoltaic, optical absorption switching and infrared modulator optical communication.

scholarly journals Triple-Band Anisotropic Perfect Absorbers Based on α-Phase MoO3 Metamaterials in Visible Frequencies

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 2061
Author(s):  
Bin Tang ◽  
Neigang Yang ◽  
Xianglian Song ◽  
Gui Jin ◽  
Jiangbin Su
Keyword(s):  
Fdtd Method ◽  
Metamaterial Absorber ◽  
Geometrical Parameters ◽  
Absorption Bands ◽  
Perfect Absorption ◽  
Dielectric Layers ◽  
Α Phase ◽  
Photo Detectors ◽  
Resonant Grating ◽  
Triple Band

Anisotropic materials provide a new platform for building diverse polarization-dependent optical devices. Two-dimensional α-phase molybdenum trioxides (α-MoO3), as newly emerging natural van der Waals materials, have attracted significant attention due to their unique anisotropy. In this work, we theoretically propose an anisotropic perfect metamaterial absorber in visible frequencies, the unit cell of which consists of a multi-layered α-MoO3 nanoribbon/dielectric structure stacked on a silver substrate. Additionally, the number of perfect absorption bands is closely related to the α-MoO3 nanoribbon/dielectric layers. When the proposed absorber is composed of three α-MoO3 nanoribbon/dielectric layers, electromagnetic simulations show that triple-band perfect absorption can be achieved for polarization along [100], and [001] in the direction of, α-MoO3, respectively. Moreover, the calculation results obtained by the finite-difference time-domain (FDTD) method are consistent with the effective impedance of the designed absorber. The physical mechanism of multi-band perfect absorption can be attributed to resonant grating modes and the interference effect of Fabry–Pérot cavity modes. In addition, the absorption spectra of the proposed structure, as a function of wavelength and the related geometrical parameters, have been calculated and analyzed in detail. Our proposed absorber may have potential applications in spectral imaging, photo-detectors, sensors, etc.

Very High Q-Factor Based On G-Shaped Resonator Type Metamaterial Absorber

2018 ◽  
pp. 160 ◽  
Author(s):  
Khalid Saeed Lateef Al-Badri
Keyword(s):  
Resonance Frequency ◽  
Metamaterial Absorber ◽  
Q Factor ◽  
High Q ◽  
Image Sensing ◽  
At Resonance ◽  
Band Filter ◽  
Simulation Results ◽  
Very High ◽  
Triple Band

High Q-factor based on absorption can be achieved by tuning (the reflection and the transition percentage). In this work, the simple design and simulated in S-band have been investigated. The simulation results of G-shape resonator are shown triple band of absorption peaks 60%, 91.5%, and 70.3%) at resonance frequency 2.7 GHz, 3.26 GHz, and 4.05 GHz respectively. The results exhibited very high of the Q-factor ( 271 ) at resonance frequency ( 3.26 GHz ).  The high Q-factor can be used to enhance the sensor sensing, narrowband band filter and  image sensing.

Sign in / Sign up

Export Citation Format

Share Document