Investigation of In-Gap Field Enhancement at Terahertz Frequencies for a Metasurface Enhanced Sensor

The arrangements of subwavelength inclusions in a metasurface can serve as an effective absorber for the terahertz region. When such an absorber is combined with a unique material, the absorption can induce effects that can lead to a change in the materials electrical properties. Vanadium dioxide shows a passive and reversible change from monoclinic insulator phase to metallic tetragonal rutile structure by using external stimuli such as temperature (340K), photo excitation, electric field, mechanical strain or magnetic field [1] , [2] . Upon absorption of the THz radiation, the high electric fields that are generated inside the gaps of the metasurface can serve as trigger points, as was shown previously using kV strength THz E-fields [1] . By designing a better sensor which takes advantage of this non-linear enhancement one can lower this value to more accessible THz electric field strengths. In this work by utilizing various metasurface designs we examined the insulator to metal transition in VO 2 when illuminated by THz radiation. Gaps whose lengths were varied as 0.5, 1, 1.5µm that are oriented perpendicularly to the polarized THz fields served as field enhancement centers. Single and double notched gaps are compared and their respective in-gap field enhancements are calculated. In the single notched structure maximum in gap field enhancement value is obtained as nearly 100 for a 1.0µm gap size. For the double notched structure in gap field enhancement values are almost the same and maximum is obtained for 0.5µm at nearly 180 for both gaps. The change in enhancement shows that the non-linear enhancement is highly dependent on the geometry of the electrodes for a fixed unit cell wall thickness. Such enhancements can be exploited in designing sensitive sensors in the low frequency THz region.


Investigation of Porosity and Permeability Impairment in Sandstones by X-ray Analysis and Simulation
Iscan, A. G.; Kök, Mustafa Verşan; Civan, F. (Informa UK Limited, 2009-01-01)
Both porosity and permeability constitute the major parameters in core analysis. In this study, the variation of these two parameters along a sandstone core sample was investigated during formation damage. A water-based drilling fluid was dynamically circulated through the core sample for three different time intervals of 15 min, 45 min, and 60 min at 100 psi circulation pressure. The core sample was analyzed using x-ray digital radiography by sectional image approach. The differences in the porous media du...
Assessment of core-filter configuration performance of rock-fill dams under uncertainties
Çalamak, Melih; Yanmaz, Ali Melih (American Society of Civil Engineers (ASCE), 2018-04-01)
Probabilistic analyses are conducted for seepage through a rock-fill dam having two different core-filter configurations: one sloping and the other a central symmetrical core-filter arrangement. Uncertainties in core and filter are considered, assuming their hydraulic conductivities as random variables. For this purpose, finite-element software used for groundwater flow and seepage analyses is coupled with a random-number-generation algorithm. Monte Carlo simulations are performed for probabilistic seepage ...
Critical behaviour of the Raman frequency shifts in the vicinity of the lambda-phase transition in NH4Br
Yurtseven, Hasan Hamit (2006-01-01)
This study gives the temperature dependence of the Raman frequencies for the lattice mode of upsilon(7) (TA) and the internal mode of upsilon(2) close to the X-phase transition (T-lambda=234K, P=\) in NB4Br.
Measurement of the X(3872) production cross section via decays to J/psi pi(+)pi(-) in pp collisions at root s=7 TeV
Chatrchyan, S.; et. al. (Springer Science and Business Media LLC, 2013-04-01)
The production of the X(3872) is studied in pp collisions at root s = 7TeV, using decays to J/psi pi(+)pi(-), where the J/psi decays to two muons. The data were recorded by the CMS experiment and correspond to an integrated luminosity of 4.8 fb(-1). The measurements are performed in a kinematic range in which the X(3872) candidates have a transverse momentum 10 < p(T) < 50 GeV and rapidity vertical bar y vertical bar < 1.2. The ratio of the X(3872) and (2S) cross sections times their branching fractions int...
Physical Characterization of Inclusion Complexes of Triphenyl Phosphate and Cyclodextrins in Solution.
Zhang, N; Zane, CP; Chen, Y; Yıldırım, Erol; Hinks, D; Tonelli, AE; Vinueza, NR; Pasquinelli, MA (American Chemical Society (ACS), 2020-01-16)
The goal of this work is to provide physical insights into the formation and stability of inclusion complexes (ICs) in aqueous solution between cyclodextrins (CDs) and a common flame retardant, triphenyl phosphate (TPP). Quantum chemistry calculations reveal the possible energetically favorable geometries of TPP in their 1:1 IC form with α-, β-, and γ-CDs as well as their associated complexation, conformational, and interaction energies. High-resolution mass spectrometry (MS) and tandem MS were used with el...
Citation Formats
H. Altan, “Investigation of In-Gap Field Enhancement at Terahertz Frequencies for a Metasurface Enhanced Sensor,” presented at the 2021 Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC), Munich, Almanya, 2021, Accessed: 00, 2021. [Online]. Available: