A Theoretical Study for Designing Optical Multilayer Films Using NdF3/ ThF4

Iraqi Journal of Science ◽

10.24996/ijs.2021.62.11.9 ◽

2021 ◽

pp. 3877-3887

Author(s):

Zainab I. Al-Assadi

Keyword(s):

Refractive Index ◽

Solar System ◽

Visible Region ◽

Cost Effective ◽

Dielectric Materials ◽

High Refractive Index ◽

Efficient Design ◽

Solar Systems ◽

Merit Factor ◽

Quarter Wave

An idea of a colored glaze is presented in this study to hide and dispose all the obstacles of using solar systems as facades integrated with buildings. This aim is achieved by designing multilayer optical interference filters by using Mat lab program . Appropriate dielectric materials, namely NdF3 of high refractive index (nH =1.6) and ThF4 of low refractive index (nL =1.5143) were employed. Quarter wave thicknesses of high (H) and low (L) refractive index were deposited on a microscopic slide substrate with n=1.513 and 550 nm design wavelength (l°). Two optical models were designed, which are Air//HL//glass and Air//LH//glass, for even numbers of layers (2-32 layers). The challenge in this study is to find the most efficient design which has lower solar reflectance (Rsol.) and higher solar transmittance (Tsol.) to raise the efficiency of the solar systems and, in parallel, obtain the colored reflection to achieve the esthetic appearance of the buildings integrated with the solar system facades. The Tsol. value was high (94-95 %), whereas the Rsol. was very low (4-5 %). Hence, the efficiency of the solar system was increased. The two optical models exhibited green color reflectance in the visible region. The first design, i.e. Air/HL/glass, showed higher values of Rvis. and the merit factor (M) than the second model, resulting in a higher potential of coloration. The first design requires fewer materials and layers, thus, it is more cost-effective as compared to the second one.

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Raman scattering in high-refractive-index nanostructures

Nanophotonics ◽

10.1515/nanoph-2020-0539 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Søren Raza ◽

Anders Kristensen

Keyword(s):

Raman Spectroscopy ◽

Refractive Index ◽

Raman Scattering ◽

Bound States ◽

Stimulated Raman Scattering ◽

Dielectric Materials ◽

High Refractive Index ◽

Surface Enhanced Raman Spectroscopy ◽

Raman Enhancement ◽

The Impact

AbstractThe advent of resonant dielectric nanomaterials has provided a new path for concentrating and manipulating light on the nanoscale. Such high-refractive-index materials support a diverse set of low-loss optical resonances, including Mie resonances, anapole states, and bound states in the continuum. Through these resonances, high-refractive-index materials can be used to engineer the optical near field, both inside and outside the nanostructures, which opens up new opportunities for Raman spectroscopy. In this review, we discuss the impact of high-refractive-index nano-optics on Raman spectroscopy. In particular, we consider the intrinsic Raman enhancement produced by different dielectric resonances and their theoretical description. Using the optical reciprocity theorem, we derive an expression which links the Raman enhancement to the enhancement of the stored electric energy. We also address recent results on surface-enhanced Raman spectroscopy based on high-refractive-index dielectric materials along with applications in stimulated Raman scattering and nanothermometry. Finally, we discuss the potential of Raman spectroscopy as a tool for detecting the optical near-fields produced by dielectric resonances, complementing reflection and transmission measurements.

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Electronic and Optical Properties of Indium Selenide Nanosheet Using First-Principle Calculations

Advanced Science Engineering and Medicine ◽

10.1166/asem.2019.2464 ◽

2019 ◽

Vol 11 (11) ◽

pp. 1148-1154

Author(s):

Hamza A. Mezerh ◽

Kadhim J. Kadhim ◽

Hamad Rahman Jappor

Keyword(s):

Refractive Index ◽

Optical Properties ◽

Density Functional ◽

Visible Region ◽

High Refractive Index ◽

Indium Selenide ◽

Experimental Investigations ◽

Ultraviolet Region ◽

Electronic And Optical Properties ◽

Index Value

Density functional theory (DFT) have been used to examine the electronic and optical, properties of two-dimensional (2D) indium selenide (InSe) nanosheet. Our calculations indicate that the energy band gap of InSe is indirect and equal to 1.53 eV. It can be seen that for the pristine case, the majority and minority density of state (DOS) are fully symmetric. The optical properties are considered up to 36 eV. Our results established that the absorption starts in the visible region, while the peaks in the ultraviolet region. The refractive index value is 1.84 at zero photon energy limit and increase to 2.31. The high refractive index allows this nanosheet to be utilized as an internal layer coating between the substrate and the ultraviolet absorbing layer. Additionally, we observed that the gained optical properties of InSe nanosheet are in the ultraviolet range and the results are significant. It is expected that from these calculations to provide useful information for further experimental investigations of InSe nanosheet.

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Cold mirror based on High-Low-High refractive index dielectric materials

10.18287/1613-0073-2017-1900-5-9 ◽

2017 ◽

Author(s):

Vadim Elyutin ◽

◽

Muhammad A. Butt ◽

Svetlana N. Khonina ◽

◽

...

Keyword(s):

Refractive Index ◽

Dielectric Materials ◽

High Refractive Index

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Enhancing the aesthetic aspect of the solar systems used as facades for building by designing multi-layer optical coatings

Technium: Romanian Journal of Applied Sciences and Technology ◽

10.47577/technium.v3i11.5324 ◽

2021 ◽

Vol 3 (11) ◽

pp. 1-10

Author(s):

Zainab I. AL-Assadi ◽

Fawzia Irhayyim AL-Assadi

Keyword(s):

Refractive Index ◽

Solar Energy ◽

Energy Systems ◽

Dielectric Materials ◽

Optical Coatings ◽

Solar Systems ◽

Building Facades ◽

Aesthetic Aspect ◽

The Aesthetic ◽

Effective Integration

The design of zero-energy buildings can be depending on the effective integration of solar energy systems with building envelopes, where these systems save heat and electricity as well as enhance the aesthetic aspect of the facades. In this paper, the aspects related to the effective integration of buildings with solar energy systems (solar cells and collectors) will be discussed, as well as enhancing the aesthetic aspect of the facades, and since solar energy systems are visible to everyone, their design must adapt to the building structure and the surrounding environment. Solar energy system designers, architects, physicists and other contributors to building energy envelopes must consider the comprehensive concept of it, where buildings are part of the human and social environment and in close relationship with the natural environment, through the use of thin films technology through the design of multi-layers colored optical coatings covering solar panels for building facades. Accordingly, the energy sector should be seen as an area of aesthetic creativity. Two dielectric materials were used, the first is ThF4 with a high refractive index (1.5143) and the second is LiF with a low refractive index (1.393) and for several odd layers, starting from 3 layers and up to 21 layers and for a thicknesses of a quarter wavelength. The design Air/L/H/Glass was applied by the Mat Lab program for the seven colors of the spectrum, So, the aim of this research is determined in designing colored optical coatings for solar systems that enhance the aesthetic aspect of building facades, as well as generating thermal and electrical energy needed to operate the buildings and to find out which color has the best visible reflectivity and solar transmittance better than the rest of the spectrum, all the results exhibit that yellow color has the higher visible reflectivity and higher merit factor, so it is consider the most efficient color for coloring the solar systems than the rest of colors spectrum.

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The Quest for Low Loss High Refractive Index Dielectric Materials for UV Photonic Applications

Applied Sciences ◽

10.3390/app8112065 ◽

2018 ◽

Vol 8 (11) ◽

pp. 2065 ◽

Cited By ~ 5

Author(s):

Yael Gutiérrez ◽

Dolores Ortiz ◽

José Saiz ◽

Francisco González ◽

Pablo Albella ◽

...

Keyword(s):

Refractive Index ◽

Near Infrared ◽

Numerical Study ◽

Near Field ◽

Field Enhancement ◽

Dielectric Materials ◽

High Refractive Index ◽

Heat Radiation ◽

Aluminum Phosphide ◽

Spectral Ranges

Nanostructured High Refractive Index (HRI) dielectric materials, when acting as nanoantennas or metasurfaces in the near-infrared (NIR) and visible (VIS) spectral ranges, can interact with light and show interesting scattering directionality properties. Also, HRI dielectric materials with low absorption in these spectral ranges show very low heat radiation when illuminated. Up to now, most of the studies of these kind of materials have been explored in the VIS-NIR. However, to the best of our knowledge, these properties have not been extended to the ultraviolet (UV), where their application in fields like photocatalysis, biosensing, surface-enhanced spectroscopies or light guiding and trapping can be of extraordinary relevance. Here, we present a detailed numerical study of the directional scattering properties, near-field enhancement and heat generation of several materials that can be good candidates for those applications in the UV. These materials include aluminum phosphide, aluminum arsenide, aluminum nitride, diamond, cerium dioxide and titanium dioxide. In this study, we compare their performance when forming either isolated nanoparticles or dimers to build either nanoantennas or unit cells for more complex metasurfaces.

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Color Glass by Layered Nitride Films for Building Integrated Photovoltaic (BIPV) System

10.20944/preprints202102.0190.v1 ◽

2021 ◽

Author(s):

Akpeko Gasonoo ◽

Hyeon-Sik Ahn ◽

Seongmin Lim ◽

Jae-Hyun Lee ◽

Yoonseuk Choi

Keyword(s):

Refractive Index ◽

Cost Effective ◽

Optical Transmittance ◽

High Refractive Index ◽

Multilayer Films ◽

Target Thickness ◽

Color Glass ◽

Significant Difference ◽

Building Integrated Photovoltaic ◽

Refractive Index Layer

We investigated layered titanium nitride (TiN) and aluminum nitride (AlN) for color glasses in Building Integrated Photovoltaic (BIPV) systems. AlN and TiN are among suitable and cost-effective optical materials to be used as thin multilayer films, owing to the significant difference in their refractive index. To fabricate the structure, we used radio frequency magnetron deposition method to achieve the target thickness uniformly. A simple, fast, and cheap fabrication method is achieved by depositing the multilayer films in a single sputtering chamber. It is demonstrated that a multilayer stack that allows light to move from a low refractive index layer to a high refractive index layer or vice-versa can effectively create various distinct color reflections for different film thicknesses and multilayer structures. It is investigated from simulation based on wave optics that, TiN/AlN multilayer offers better color design freedom and cheaper fabrication process as compared to AlN/TiN multilayer films. Blue, green, and yellow color glasses with optical transmittance of more than 80% was achieved by ITO coated glass/TiN/AlN multilayer films. This technology exhibits good potential in commercial BIPV system applications.

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Triethylene glycol–titanium oxide hydrate hybrid films with high refractive index and surface evenness

Journal of Materials Chemistry C ◽

10.1039/c3tc32200a ◽

2014 ◽

Vol 2 (22) ◽

pp. 4468-4475 ◽

Cited By ~ 8

Author(s):

Seung Koo Park ◽

Byoung-Kuk Kang ◽

Jin-Wook Shin ◽

Chul Woong Joo ◽

Jaehyun Moon ◽

...

Keyword(s):

Refractive Index ◽

Titanium Oxide ◽

Hybrid Film ◽

Sintering Temperature ◽

Visible Region ◽

Triethylene Glycol ◽

High Refractive Index ◽

Hybrid Films ◽

Oxide Hydrate ◽

Lower Temperature

An organic–inorganic hybrid film fabricated from triethylene glycol–titanium oxide hydrate solution shows high refractive index (n ∼ 2.1) in the visible region and surface evenness (Ra ∼ 0.25 nm) even when it is annealed at much lower temperature than the sintering temperature of titanium dioxide.

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High refractive index and extreme biaxial optical anisotropy of rhenium diselenide for applications in all-dielectric nanophotonics

Nanophotonics ◽

10.1515/nanoph-2020-0416 ◽

2020 ◽

Vol 9 (16) ◽

pp. 4737-4742

Author(s):

Anton A. Shubnic ◽

Roman G. Polozkov ◽

Ivan A. Shelykh ◽

Ivan V. Iorsh

Keyword(s):

Refractive Index ◽

Dimensionless Parameter ◽

Dielectric Materials ◽

High Refractive Index ◽

Wide Frequency Range ◽

Visible Range ◽

Low Loss ◽

Optical Susceptibility ◽

Valence Bands ◽

Rhenium Diselenide

AbstractWe establish a simple quantitative criterium for the search of new dielectric materials with high values of refractive index in the visible range. It is demonstrated, that for light frequencies below the bandgap, the latter is determined by the dimensionless parameter η calculated as the ratio of the sum of the widths of conduction and valence bands and the bandgap. Small values of this parameter, which can be achieved in materials with almost flat bands, lead to dramatic increase of the refractive index. We illustrate this rule with a particular example of rhenium dichalcogenides, for which we perform ab initio calculations of the band structure and optical susceptibility and predict the values of the refractive index $n{ >}5$ in a wide frequency range around 1 eV together with comparatively low losses. Our findings open new perspectives in search for the new high-index/low-loss materials for all-dielectric nanophotonics.

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