scholarly journals Gap-Size-Dependent Effective Phase Transition in Metasurfaces of Closed-Ring Resonators

Crystals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 684
Author(s):  
Seojoo Lee ◽  
Ji-Hun Kang
Keyword(s):  
Lattice Spacing ◽  
Effective Permittivity ◽  
Ring Resonators ◽  
Size Dependent ◽  
Closed Ring ◽  
Resonant Behavior ◽  
Tightly Coupled ◽  
Metal To Insulator Transition ◽  
Effective Phase ◽  
2D Crystals

We theoretically investigate a metal-to-insulator transition in artificial two-dimensional (2D) crystals (i.e., metasurfaces) of tightly coupled closed-ring resonators. Strong interaction between unit resonators in the metasurfaces yields the effective permittivity highly dependent on the lattice spacing of unit resonators. Through our rigorous theory, we provide a closed form of effective permittivity of the metasurface and reveal that the permittivity possesses a Lorentzian-type resonant behavior, implying that the transition of the effective permittivity can arise when the lattice spacing passes a critical value.

Design Considerations Pertaining to the Application of Complementary Split Ring Resonators in Microstrip Antennas

2019 ◽  
pp. 25-56
Author(s):  
Sivaranjan Goswami ◽  
Kumaresh Sarmah ◽  
Angana Sarma ◽  
Kandarpa Kumar Sarma ◽  
Sunandan Baruah
Keyword(s):  
Effective Permittivity ◽  
Microstrip Antennas ◽  
Negative Permittivity ◽  
Ring Resonators ◽  
Dual Band ◽  
Split Ring ◽  
Complementary Split Ring Resonator ◽  
Dual Band Antennas ◽  
Notch Filtering ◽  
Filtering Element

Metamaterial-based design of microstrip antennas and other microwave structures have gained enormous popularity worldwide among researchers. The complementary split ring resonator (CSRR) is one of the most commonly used metamaterial structures in this direction. The CSRR structure yields a negative value of its effective permittivity at a narrow band near its resonant frequency. CSRR structure was initially proposed as a notch filtering element in microstrip transmission lines because of the negative permittivity. Later, the CSRR structure found its use in antennas and other microwave applications. The CSRR structure is reported to enhance the performance of a microstrip antenna in terms of its gain and bandwidth. In addition, CSRR structure is also used in the design of dual band antennas and antennas with integrated filters. This chapter deals with the practical design aspects relative to these applications of CSRR structures.

Optically Transparent Broadband Microwave Absorption Metamaterial By Standing-Up Closed-Ring Resonators

2017 ◽  
Vol 5 (13) ◽  
pp. 1700109 ◽  
Author(s):  
Dawei Hu ◽  
Jie Cao ◽  
Wei Li ◽  
Cheng Zhang ◽  
Tianlong Wu ◽  
...  
Keyword(s):  
Microwave Absorption ◽  
Ring Resonators ◽  
Closed Ring ◽  
Optically Transparent ◽  
Standing Up

scholarly journals Size-dependent movement explains why bigger is better in fragmented landscapes

2018 ◽  
Author(s):  
Jasmijn Hillaert ◽  
Thomas Hovestadt ◽  
Martijn L. Vandegehuchte ◽  
Dries Bonte
Keyword(s):  
Body Size ◽  
Size Variation ◽  
The Body ◽  
Individual Development ◽  
Size Distributions ◽  
Fragmented Landscapes ◽  
Strong Selection ◽  
Size Dependent ◽  
Two Factors ◽  
Tightly Coupled

AbstractBody size is a fundamental trait known to allometrically scale with metabolic rate, and therefore a key determinant of individual development, life history and consequently fitness. In spatially structured environments, movement is an equally important driver of fitness. Because movement is tightly coupled with body size, we expect habitat fragmentation to induce a strong selection pressure on size variation across and within species. Changes in body size distributions are then, in turn, expected to alter food web dynamics. However, no consensus has been reached on how spatial isolation and resource growth affect body size distributions.Our aim was to investigate how these two factors shape the body size distribution of consumers under scenarios of size-dependent and -independent consumer movement by applying a mechanistic, individual-based resource-consumer model. The outcome was then linked to important ecosystem traits such as resource abundance and stability. Finally, we determined those factors that explain most variation in size distributions.We demonstrate that decreasing connectivity and resource growth select for communities (or populations) consisting of larger species (or individuals) due to strong selection for the ability to move over longer distances. When including size-dependent movement, moderate levels of connectivity result in increases in local size diversity. Due to this elevated functional diversity, resource uptake is optimized at the metapopulation or metacommunity level. At these intermediate levels of connectivity, size-dependent movement explains most of the observed variation in size distributions. Interestingly, local and spatial stability of consumer biomass are lowest when isolation and resource productivity are high. Finally, we highlight that size-dependent movement is of vital importance for the survival of populations within highly fragmented landscapes. Our results demonstrate that considering size-dependent movement and resource growth is essential to understand patterns of size distributions at the population or community level and the resulting metapopulation or metacommunity dynamics.

Coupled ring resonator for microwave characterization of dielectric materials

2012 ◽  
Vol 4 (2) ◽  
pp. 241-246 ◽  
Author(s):  
Mahima Kapoor ◽  
K. S. Daya ◽  
G. S. Tyagi
Keyword(s):  
Dielectric Constant ◽  
Spirulina Platensis ◽  
Ring Resonator ◽  
Dielectric Materials ◽  
Split Ring Resonator ◽  
Ring Resonators ◽  
Split Ring ◽  
Split Ring Resonators ◽  
Closed Ring

In this paper characterization of dielectric materials in liquid and powder phase using concentric closed and split ring resonators of length λ, λ/2, and λ/4 is reported. Experimental results have been validated by simulations and theoretically modeling. Sensitivity of the resonator with closed rings was maximum. Experimentally extracted values of dielectric constant of ferrite ranged from 14.05 to 15.1 with closed ring resonators and from 13.6 to 14.02 with split ring resonator, respectively. For spirulina platensis the dielectric constant was lying in the range 1.78–1.93 and 1.74–2.04 with closed ring and split ring resonators, respectively. The values extracted experimentally are in good agreement with simulation and theoretically found values. However, the values obtained from closed ring resonator were in agreement with the dielectric constant values of ferrite and spirulina platensis.

Switchable square ring bandpass to bandstop filter for ultra-wideband applications

2015 ◽  
Vol 9 (1) ◽  
pp. 51-60
Author(s):  
Mushtaq Alqaisy ◽  
Chandan K. Chakrabraty ◽  
Jawad K. Ali ◽  
Adam Reda Alhawari ◽  
Tale Saeidi
Keyword(s):  
Computer Simulation ◽  
Radio Frequency ◽  
Ultra Wideband ◽  
Ring Resonators ◽  
Microstrip Filter ◽  
Filter Structure ◽  
Closed Ring ◽  
Effective Cost ◽  
Bandstop Filter ◽  
Good Agreement

In this manuscript, serial-shunt of square ring resonators with step-impedance open circuited stub resonators to produce a new on-off switchable bandpass to bandstop response in the same ultra-wideband microstrip filter structure is proposed. The closed ring of series-shunt square ring resonators with a combine stubs are introduced to excite the bandpass response while bandstop characteristic excited when gaps are embedded in the corners of the square ring resonators. The main advantage of this microstrip filter is its capability to switch from bandpass-to-bandstop operation using open-short gap, respectively. A microwave simulator is utilized to show the switchable case by replacing Skyworks radio frequency diodes (RF-PIN) instead of those gaps. The entire filter models have been simulated using the computer simulation technology (CST) Microwave Studio. The computed results for the proposed filters were compared with the measured results of the both prototype structures (bandpass- and bandstop-filter). The codes also showed good agreement between them. Other advantages include being small in size, and low in effective cost.

A reconfigurable bandpass-bandstop filter based on varactor-loaded closed-ring resonators [Technical Committee]

2009 ◽  
Vol 10 (1) ◽  
pp. 138-140 ◽  
Author(s):  
Yi-Ming Chen ◽  
Sheng-Fuh Chang ◽  
Cheng-Yu Chou ◽  
Kun-Hsing Liu
Keyword(s):  
Technical Committee ◽  
Ring Resonators ◽  
Closed Ring ◽  
Bandstop Filter

Extraordinary terahertz transmission through a double-layer metal array with closed ring resonators

2016 ◽  
Vol 370 ◽  
pp. 256-262 ◽  
Author(s):  
Yadong Guo ◽  
Zongheng Yuan ◽  
Yuyang Yuan ◽  
Sheng Wang ◽  
Wentao Zhang
Keyword(s):  
Double Layer ◽  
Ring Resonators ◽  
Closed Ring ◽  
Terahertz Transmission
Sign in / Sign up

Export Citation Format

Share Document