Study and Simulation of a Sensor Based on 2D Photonic Crystals for the Detection of Aromatic Compounds: C6H5I, C6H5F and C6H5Cl

A new study was presented on a new sensor based on two-dimensional photonic crystals (Phc's) to detect the following three organic materials: iodobenzene (C6H5I), fluorobenzene (C6H5F), chlorobenzene (C6H5Cl). These materials have dielectric constants (εr) equal to 2.623; 2.140; 2.318, respectively. The proposed sensor is a structure made of silicon rods submerged in air plus a ring resonator. The ring resonator is stuck between two horizontal waveguides. At the end of the ends of the structure there are four ports where port 1 and 2 belong to the top guide and port (3) and (4) the bottom one. In order to analyze the behavior of the sensor, a plane wave expansion approach (PWE) and the finite element method (FEM) are applied. Thanks to the MATLAB and COMSOL simulation software, we were able to obtain the following numerical results: the norm of the electric field, the total energy density and this last magnitude according to the refractive indices of the different organic materials used. We could observe variations in energy density for each material. So, this change is due to their refractive index which varies from one material to another. In this study, we have fixed the other parameters like the constant of the lattice "a" and the radius "r" and we are interested in the dielectric constants (εr) or more precisely the refractive index (n), the latter proves that it is one of the important parameters for detection.

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Performance of the Active Microring Resonator Based on SOI Rib Waveguide

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.462.375 ◽

2012 ◽

Vol 462 ◽

pp. 375-379

Author(s):

B. Mardiana ◽

A.R. Hanim ◽

H. Hazura ◽

S. Shaari ◽

P. Susthitha Menon ◽

...

Keyword(s):

Refractive Index ◽

Ring Resonator ◽

Refractive Index Change ◽

Electrical Signal ◽

Free Carrier ◽

Simulation Software ◽

Microring Resonator ◽

Silicon On Insulator ◽

Carrier Injection ◽

Rib Waveguide

Micro-ring resonator based on silicon-on-insulator (SOI) has been extensively studied due to its many advantages, thus promising to improve the optoelectronic integrated circuit performance. This paper highlights the study of the free carrier injection effect on the silicon rib waveguide with p-i-n diode structure integrated in the SOI micro-ring resonator. The free carrier concentrations have been modulated by the electrical signal that can cause change of refractive index of the micro-ring resonator. The device performances are predicted by using numerical modelling software 2D SILVACO and Finite Difference Time Domain method simulation software RSOFT. The results show the change of refractive index is maximized at a greater applied voltage. A shift in resonant wavelength of around 6.7 nm was predicted at 0.9V with 1.14x10-3refractive index change. It is also shown that 8.5dB change of the output response obtained through the output.

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Analysis On Thermal Behaviour Of The Sink And Die Area With Different Thermal Interface Material For High Power Light Emitting Diodes

Light & Engineering ◽

10.33383/2019-096 ◽

2020 ◽

pp. 116-126

Author(s):

Debashis Raul ◽

Kamalika Ghosh

Keyword(s):

Light Emitting Diodes ◽

Simulation Software ◽

Thermal Interface Material ◽

Junction Temperature ◽

Heating Process ◽

Thermal Interface ◽

Light Emitting ◽

Materials Used ◽

Comsol Simulation ◽

Interface Materials

Its self-heating process directly affects the optical performance and reliability of light – emitting diodes (LEDs). It is important to disperse the generated heat from LED to surrounding atmosphere and keep the LED light performances same as declared by the manufacturer. Thermal interface material (TIM) is applied in between sink and source to reduce contact resistance at the junction between substrate and heat sink interface of the LED modules. This paper provides an assessment on ‘thermal interface materials’. Here different TIM materials used and the performance and problems of these commercial interface materials are discussed. From this study, one can calculate the temperature distribution in the sink area for different types of TIM materials under thermal conductivity perspective and be able to find the capability of dissipation of heat at the end surfaces of heat sinks, and design their system as well. In another process, TIMs with different thickness and input drive currents for the COB-based LED are investigated by using COMSOL simulation software. The results show that the junction temperature of the LED luminaire increases and reduce the lifetime when the input drive current and thickness of the TIM layers increase.

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Active SOI Optical Ring Resonator Based on Free Carrier Injection

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.403-408.758 ◽

2011 ◽

Vol 403-408 ◽

pp. 758-761

Author(s):

B. Mardiana ◽

A.R. Hanim ◽

H. Hazura ◽

S. Shaari ◽

P. Susthitha Menon ◽

...

Keyword(s):

Refractive Index ◽

Ring Resonator ◽

Refractive Index Change ◽

Free Carrier ◽

Simulation Software ◽

Carrier Injection ◽

Index Change ◽

N Doping ◽

Optical Ring ◽

Optical Ring Resonator

This paper highlights the study of the free carrier injection effect on the active SOI optical ring resonator. The effect of the free carrier injection on optical ring resonator was evaluated by varying the p+ and n+ doping concentrations. The device performances are predicted by using numerical modelling software of the 2D SILVACO and Finite Difference Time Domain method simulation software RSOFT. The results show the refractive index change increases as the p+and n+doping concentrations is getting higher. A shift in resonant wavelength of around 2 nm was predicted at 5x1019cm3p+and n+doping concentrations with 5.8x10-3refractive index change. It is also shown that 8.2dB change of the output response obtained through the output.

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Effects of geometric and refractive index disorder on wave propagation in two-dimensional photonic crystals

Physical Review E ◽

10.1103/physreve.62.5711 ◽

2000 ◽

Vol 62 (4) ◽

pp. 5711-5720 ◽

Cited By ~ 47

Author(s):

A. A. Asatryan ◽

P. A. Robinson ◽

L. C. Botten ◽

R. C. McPhedran ◽

N. A. Nicorovici ◽

...

Keyword(s):

Refractive Index ◽

Wave Propagation ◽

Photonic Crystals ◽

Two Dimensional

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Life Cycle Environmental Assessment of Light Steel Framed Buildings with Cement-Based Walls and Floors

Sustainability ◽

10.3390/su122410686 ◽

2020 ◽

Vol 12 (24) ◽

pp. 10686

Author(s):

Mona Abouhamad ◽

Metwally Abu-Hamd

Keyword(s):

Life Cycle ◽

Building Materials ◽

Simulation Software ◽

Life Cycle Assessment Methodology ◽

Building Information Model ◽

Building Information ◽

Cold Formed Steel ◽

Environmental Measures ◽

Materials Used

The objective of this paper is to apply the life cycle assessment methodology to assess the environmental impacts of light steel framed buildings fabricated from cold formed steel (CFS) sections. The assessment covers all phases over the life span of the building from material production, construction, use, and the end of building life, in addition to loads and benefits from reuse/recycling after building disposal. The life cycle inventory and environmental impact indicators are estimated using the Athena Impact Estimator for Buildings. The input data related to the building materials used are extracted from a building information model of the building while the operating energy in the use phase is calculated using an energy simulation software. The Athena Impact Estimator calculates the following mid-point environmental measures: global warming potential (GWP), acidification potential, human health potential, ozone depletion potential, smog potential, eutrophication potential, primary and non-renewable energy (PE) consumption, and fossil fuel consumption. The LCA assessment was applied to a case study of a university building. Results of the case study related to GWP and PE were as follows. The building foundations were responsible for 29% of the embodied GWP and 20% of the embodied PE, while the CFS skeleton was responsible for 30% of the embodied GWP and 49% of the embodied PE. The production stage was responsible for 90% of the embodied GWP and embodied PE. When benefits associated with recycling/reuse were included in the analysis according to Module D of EN 15978, the embodied GWP was reduced by 15.4% while the embodied PE was reduced by 6.22%. Compared with conventional construction systems, the CFS framing systems had much lower embodied GWP and PE.

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Infrared Intensities of Liquids XX: The Intensity of the OH Stretching Band of Liquid Water Revisited, and the Best Current Values of the Optical Constants of H2O(l) at 25°C between 15,000 and 1 cm−1

Applied Spectroscopy ◽

10.1366/0003702963905385 ◽

1996 ◽

Vol 50 (8) ◽

pp. 1047-1057 ◽

Cited By ~ 392

Author(s):

John E. Bertie ◽

Zhida Lan

Keyword(s):

Refractive Index ◽

Liquid Water ◽

Peak Height ◽

Dielectric Constants ◽

The Real ◽

Infrared Intensities ◽

Refractive Index Spectrum ◽

Relative Errors ◽

Integrated Intensities ◽

Normal Laboratory

The previously reported nonreproducibility of the intensity of the OH stretching band of liquid water has been explored. It was found that it can be eliminated in measurements with the Circle® multiple ATR cell by ensuring that the ATR rod is coaxial with the glass liquid holder. It was also found that normal laboratory temperature variations of a few degrees change the intensity by ⩽∼1% of the peak height. A new imaginary refractive index spectrum of water has been determined between 4000 and 700 cm1 as the average of spectra calculated from ATR spectra recorded by four workers in our laboratory over the past seven years. It was obtained under experimental and computational conditions superior to those used previously, but is only marginally different from the spectra reported in 1989. In particular, the integrated intensities of the fundamentals are not changed significantly from those reported in 1989. The available imaginary refractive index, k, values between 15,000 and 1 cm−1 have been compared. The values that are judged to be the most reliable have been combined into a recommended k spectrum of H2O(l) at 25 °C between 15,000 and 1 cm−1, from which the real refractive index spectrum has been calculated by Kramers–Kronig transformation. The recommended values of the real and imaginary refractive indices and molar absorption coefficients of liquid water at 25 ± 1 °C are presented in graphs and tables. The real and imaginary dielectric constants and the real and imaginary molar polarizabilities in this wavenumber range can be calculated from the tables. Conservatively estimated probable errors of the recommended k values are given. The precision with which the values can be measured in one laboratory and the relative errors between regions are, of course, far smaller than these probable errors. The recommended k values should be of considerable value as interim standard intensities of liquid water, which will facilitate the transfer of intensities between laboratories.

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