Refractive index and dielectric constant transition of ultra-thin gold from cluster to Film

The influence of dispersing Al-metal complex on the optical properties of PVA was investigated using UV–visible spectroscopy. Polymer composite films with various Al3+-complex amounts in the PVA matrix were arranged by solution casting technique by means of distilled water as a widespread solvent. The formation of Al3+-metal complex was verified through Ultraviolet–visible (UV-Vis) and Fourier-transform infrared spectroscopy (FTIR) examinations. The addition of Al-complex into the polymer matrix led to the recovery of the optical parameters such as dielectric constant (εr and εi) and refractive index (n). The variations of real and imaginary parts of complex dielectric constant as a function of photon wavelength were studied to calculate localized charge density values (N/m*), high-frequency dielectric constant, relaxation time, optical mobility, optical resistivity, and plasma angular frequency (ωp) of electrons. In proportion with Al3+-complex content, the N/m* values were amplified from 3.68 × 1055 kg−1 m−3 to 109 × 1055 kg−1 m−3. The study of optical parameters may find applications within optical instrument manufacturing. The optical band gap was determined from Tauc’s equation, and the type of electronic transition was specified. A remarkable drop in the optical band gap was observed. The dispersion of static refractive index (no) of the prepared composites was analyzed using the theoretical Wemple–DiDomenico single oscillator model. The average oscillator energy (Eo) and oscillator dispersion energy (Ed) parameters were estimated.

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Effect of non-annealed and annealed ZnO on the optical properties of PVC/ZnO nanocomposite films

Journal of Thermoplastic Composite Materials ◽

10.1177/08927057211038631 ◽

2021 ◽

pp. 089270572110386

Author(s):

Ali F Al-Shawabkeh ◽

Ziad M Elimat ◽

Khaleel N Abushgair

Keyword(s):

Dielectric Constant ◽

Refractive Index ◽

Optical Properties ◽

Zno Nanoparticles ◽

Oscillator Strengths ◽

Nanocomposite Films ◽

Optical Parameters ◽

Zno Nanoparticle ◽

Dispersion Energy ◽

Optical Susceptibility

The goal of this study was to investigate the optical properties of the prepared polyvinyl chloride (PVC)/zinc oxide (ZnO) nanocomposite films. The PVC/ZnO nanocomposite films consist of the addition of different concentrations with both non-annealed ZnO nanoparticles and ZnO nanoparticles annealed at temperature of 700°C. The PVC/ZnO nanocomposite films by weight concentrations of (0 wt.%, 2.5 wt.%, 5 wt.% and 10 wt.%) have been prepared by the casting method. The optical absorbance and transmittance values of the composites films were measured in the wavelength range between (250 to 1100 nm) at room temperature by using the UV-1800 Shimadzu spectrophotometer. The optical properties (absorption coefficient, dielectric constant, refractive index, and optical conductivity) have been investigated by the ultraviolet (UV) spectrophotometer. The optical parameters (direct optical energy gap, excitation energy for electronic transitions, the dispersion energy, static refractive index, static dielectric constant, optical oscillator strengths, the moments of optical spectrum, linear optical susceptibility, third-order nonlinear optical susceptibility, nonlinear refractive index, high-frequency dielectric constant, the carrier concentration to the effective mass ratio, the long wavelength refractive index and the plasma frequency) were calculated. The results showed that the optical properties behavior of the PVC/ZnO nanocomposite films was found to be dependent on the ZnO concentration, and photon wavelength. In addition, the results of the study show that the optical parameters can be influenced by alter the concentration of the nonannealed and annealed a ZnO nanoparticle in the PVC polymer matrix.

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Study the Effect of Heat Treatment and Pressure on some the Optical Properties of the Pure PVA Nano Polymer

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.900.16 ◽

2021 ◽

Vol 900 ◽

pp. 16-25

Author(s):

Tabarak Mohammed Awad ◽

May A.S. Mohammed

Keyword(s):

Heat Treatment ◽

Dielectric Constant ◽

Refractive Index ◽

Optical Properties ◽

Absorption Coefficient ◽

Polyvinyl Alcohol ◽

Complex Dielectric Constant ◽

Different Temperatures ◽

German Origin ◽

Increasing Temperature

In this study, some optical properties were studied of the pure vinyl polyvinyl alcohol (PVA) nanopolymer (German origin). Under the influence of different temperatures and pressures of PVA. Where 25 samples were prepared for the purpose of conducting the research. Which studied the study of these samples was done by recording the absorbance and transmittance spectra of the wavelengths (200-900) nm. From them, absorbance, transmittance, reflectivity, absorption coefficient, refractive index, extinction coefficient, complex dielectric constant were calculated. At different temperatures (25,40, 80, 120, 160)°C. And with different pressures within the range (7.5,8,8.5,9,9.5) MPa. The results are that the permeability of the polymer (PVA) at different temperatures for each pressure decreases with increasing temperature, and that all other calculated optical properties increase with increasing temperature.

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Effect of thickness on the optical properties of Gaas thin films

Journal of Bangladesh Academy of Sciences ◽

10.3329/jbas.v37i1.15684 ◽

2013 ◽

Vol 37 (1) ◽

pp. 83-91 ◽

Cited By ~ 13

Author(s):

Chitra Das ◽

Jahanara Begum ◽

Tahmina Begum ◽

Shamima Choudhury

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Refractive Index ◽

Band Gap ◽

Optical Band Gap ◽

Visible Region ◽

Solar Spectrum ◽

Band Gap Energy ◽

Optical Parameters ◽

Gap Energy

Effect of thickness on the optical and electrical properties of gallium arsenide (GaAs) thin films were studied. The films of different thicknesses were prepared by vacuum evaporation method (~10-4 Pa) on glass substrates at a substrate temperature of 323 K. The film thickness was measured in situ by a frequency shift of quartz crystal. The thicknesses were 250, 300 and 500 nm. Absorption spectrum of this thin film had been recorded using UV-VIS-NIR spectrophotometer in the photon wavelength range of 300 - 2500 nm. The values of some important optical parameters of the studied films (absorption coefficient, optical band gap energy and refractive index; extinction co-efficient and real and imaginary parts of dielectric constant) were determined using these spectra. Transmittance peak was observed in the visible region of the solar spectrum. Here transmittance showed better result when thicknesses were being increased. The optical band gap energy was decreased by the increase of thickness. The refractive index increased by increasing thickness while extinction co-efficient and real and imaginary part of dielectric constant decreased. DOI: http://dx.doi.org/10.3329/jbas.v37i1.15684 Journal of Bangladesh Academy of Sciences, Vol. 37, No. 1, 83-91, 2013

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Physical and Thermodynamic Properties of Terpenes. IV. The Dielectric Constant, Refractive Index and Density of Some Terpenes1

Journal of the American Chemical Society ◽

10.1021/ja01648a026 ◽

1954 ◽

Vol 76 (19) ◽

pp. 4856-4858 ◽

Cited By ~ 14

Author(s):

Gerald A. Thomas ◽

J. Erskine Hawkins

Keyword(s):

Dielectric Constant ◽

Refractive Index ◽

Thermodynamic Properties ◽

Constant Refractive Index

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Temperaturabhängigkeit der statischen Dielektrizitätskonstante und des optischen Brechungsindexes von Flüssigkeiten

Zeitschrift für Naturforschung A ◽

10.1515/zna-1975-0304 ◽

1975 ◽

Vol 30 (3) ◽

pp. 287-291 ◽

Cited By ~ 6

Author(s):

I. Gryczyński ◽

A. Kawski

Keyword(s):

Dielectric Constant ◽

Refractive Index ◽

Dipole Moment ◽

Dipole Moments ◽

Mixed Solvents ◽

Temperature Changes ◽

Temperature Dependences ◽

Solvent Shifts ◽

Pure And Mixed Solvents ◽

Good Agreement

A variation of the temperature changes the static dielectric constant (ε) and the refractive index (n) of solvents and, in conjunction with the measurement of solvent shifts of absorption and fluorescence maxima, allows the investigation of dipole moment changes of solutes in the excited state. For this purpose, investigations of the temperature dependences of ε and n of some pure and mixed solvents of different polarities have been made. It is found that the excited dipole moments of indole, 1,2-dimethylindole, 2,3-dimethylindole and tryptophan obtained from the shifts of the fluorescence maxima in mixed solvents at high temperatures are in good agreement with those obtained in other ways.

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Preparation and Studying the Optical Properties of (Sb2o3) Thin Films

Journal of University of Babylon for Pure and Applied Sciences ◽

10.29196/jubpas.v26i10.1881 ◽

2018 ◽

Vol 26 (10) ◽

pp. 249-256

Author(s):

Waleed Khalid Kadhim

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Refractive Index ◽

Optical Properties ◽

Absorption Coefficient ◽

Thermal Evaporation ◽

Glass Slide ◽

Antimony Trioxide ◽

Hot Plate ◽

Different Thickness

In this paper I present the preparation of (Sb2o3) thin films using thermal evaporation in vacuum, procedure with different thickness (100 ,150 ,200 ,and 250) nm, by using ( hot plate) from Molybdenum matter at temperature in ( 9000c) and the period of time (15mint) ,the prepared in a manner thermal evaporation in a vacuum and precipitated on glass bases, pure Antimony Trioxide (sb2o3 ) thin films with various condition have been successfully deposited by (T.E.V) on glass slide substrates. The substrates temperature of about 100oC and the vacuum of about 10-6 torr, to investigated oxidation of evaporated, measure spectra for prepared films in arrange of wavelength (250 – 1100 nm). The following optical properties have been calculated: the absorption coefficient, the forbidden (Eg) for direct and indirect transitions "absorbance, refractive index, extinction coefficient, real and imaginary parts" of the dielectric constant.

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Annealing Effect on Some Optical Properties of Cr2O3 Thin Films Prepared by Spray Pyrolysis Technique

Baghdad Science Journal ◽

10.21123/bsj.8.2.561-565 ◽

2011 ◽

Vol 8 (2) ◽

pp. 561-565

Author(s):

Baghdad Science Journal

Keyword(s):

Thin Films ◽

Dielectric Constant ◽

Refractive Index ◽

Optical Properties ◽

Absorption Coefficient ◽

Spray Pyrolysis ◽

Annealing Temperature ◽

Spray Pyrolysis Technique ◽

Annealing Effect ◽

Before And After

Cr2O3 thin films have been prepared by spray pyrolysis on a glass substrate. Absorbance and transmittance spectra were recorded in the wavelength range (300-900) nm before and after annealing. The effects of annealing temperature on absorption coefficient, refractive index, extinction coefficient, real and imaginary parts of dielectric constant and optical conductivity were expected. It was found that all these parameters increase as the annealing temperature increased to 550°C.

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Effect of Silver Oxide Film Thickness on Some Optical Parameter

Baghdad Science Journal ◽

10.21123/bsj.11.2.690-694 ◽

2014 ◽

Vol 11 (2) ◽

pp. 690-694

Author(s):

Baghdad Science Journal

Keyword(s):

Dielectric Constant ◽

Refractive Index ◽

Oxide Film ◽

Film Thickness ◽

Silver Oxide ◽

Optical Parameter ◽

Oxide Film Thickness ◽

Chemical Spray ◽

Transmission And Absorption ◽

Different Thickness

Films of silver oxide of different thickness have been prepared by the chemical spray paralysis. Transmission and absorption spectra have recorded in order to study the effect of increasing thickness on some optical parameter such as reflectance, refractive index , and dielectric constant in its two parts . This study reveals that all these paramters affect by increasing the thickness .

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Improve the Hole Size-dependent Refractive Index Sensitivity of Au-Ag Nanocages by Tuning the Alloy Composition

10.21203/rs.3.rs-482206/v1 ◽

2021 ◽

Author(s):

Jianjun LI ◽

Qiu-Xiang Qin ◽

Guo-Jun Weng ◽

Jian Zhu ◽

Jun-Wu Zhao

Keyword(s):

Dielectric Constant ◽

Refractive Index ◽

Electric Field ◽

Alloy Composition ◽

Geometric Parameters ◽

Sensitivity Factor ◽

Hole Size ◽

Refractive Index Sensitivity ◽

Electric Field Direction ◽

Index Sensitivity

Abstract In this study, the nanoboxes is converted into Au-Ag alloy nanocages by increasing the hole size. Discrete dipole approximation (DDA) is used to study the extinction spectrum and the refractive index sensing characteristics of Au-Ag alloy nanocages with different geometric parameters. With the increase of Au component, the local surface plasmon resonance (LSPR) peak shows approximately linear redshift and the sensitivity factor shows approximately linear decrease. The refractive index sensitivity can be effectively controlled by the Au-Ag ratio at large hole size because the hole and cavity surfaces distribute more environmental dielectric components. Therefore, increasing the hole size and decreasing the Au-Ag ratio can improve the refractive index sensitivity. To explain the effect of alloy composition on the LSPR characteristics and the refractive index sensitivity, the local electric field distributions with different geometric parameters are plotted. We find that the electric field direction on the hole and cavity surfaces are controlled by the Au-Ag ratio and environmental dielectric constant. Moreover, the field vector on the hole and cavity surfaces are formed by the superposition of the incident field, the electric field generated by the oscillating electrons on the outer surface, and the polarized field in the environmental dielectric constant.

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