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Structural, morphological, and optical properties of AgxO thin films deposited via obliquely angle deposition

Soltane H. Ben, Akkari F. Chaffar, Gallas B., Kanzari M.

Materials Science Poland

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2023

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Vol. 41, No. 1

27--41

EN

This work reports on the optical, structural, and morphological properties of silver oxide thin films obtained by postoxidation of silver deposited previously by the thermal evaporation technique. The samples were deposited on glass substrates using the oblique angle deposition technique for different angles of incidence γ (γ=0°, 20°, 40°, 60°, 75°, and 85°). γ is defined as the angle between the particle flux and the normal to the substrate. The resulting thin films were annealed in the free air at two temperatures (300°C and 400°C). X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-visible-NIR spectrophotometer were performed to study the crystal structure, as well as the morphological and optical properties (transmittance and reflectance), of the AgxO samples. X-ray diffraction analysis revealed the presence of the AgxO phase for the silver films deposited at a high angle of incidence and for the annealing temperature 300°C. In contrast, the diffractograms of the silver films annealed at 400°C show an amorphous behavior. Optical results indicated that the direct band gap energy increases pursuant to increasing the angle of incidence γ. The absorption coefficients of AgxO thin films were found to be in the range of 103–105 cm−1. Additionally, we determined the birefringence for the layers annealed at 400°C and found that the highest value of birefringence is obtained corresponding to the angle of incidence 60°. Morphological analysis indicated that the porosity increases with the angle of incidence and highlights the amorphous nature of the films, which is attributed to the columnar structure.

2

Telecommunication filter based on the symmetrical photonic crystal Bg5/Cu1/Bg5

Baraket Z., Zaghdoudi J., Kanzari M.

Optica Applicata

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2018

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Vol. 48, nr 3

361--371

EN

Thanks to the transfer matrix method, we perform a theoretical investigation of the optical properties of the symmetrical photonic crystal designed as Bg5/Cu1/Bg5, where Cu1 is the first generation of the copper mean sequence and Bg5 is the fifth generation of the Bragg sequence. We design a developed polychromatic filter which allows the transmission of all the telecommunication wavelengths 0.85, 1.3, and 1.55 µm at oblique incidence for both of TE and TM polarization with a high transmission rate and high quality factor. This photonic crystal can be employed in the fabrication of telecommunication devices.

3

Slowing of optical signals in generalized Cantor structure

Ben Ali N., Yusoff W., Trabelsi Y., Kanzari M.

Optica Applicata

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2018

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Vol. 48, nr 1

65--73

EN

In this paper, a simulation study of the slowing optical signals in generalized Cantor structure is proposed. The materials constituting the structure’s layers are SiO2 and the TiO2. The slowing down factor is determined using the transfer matrix method whose purpose is to study the slowing of light. We show that the slowing down factor value depends on the generalized Cantor parameters (a, b and c) and the reference wavelength λ0. These parameters are optimized to better slowing the optical signals, minimize the number and the thickness of structure’s layers. At the end of the paper we compare our results with previous research work.

4

The effect of the symmetrical deformation y = xk + 1 on the optimization of the symmetrical multiple channeled white light color filter

Baraket Z., Zaghdoudi J., Kanzari M.

Optica Applicata

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2017

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Vol. 47, nr 1

19--28

EN

In this paper, we consider a hybrid photonic crystal symmetrically deformed (Bg5/Cu3/Bg5) consisting of the third generation of the copper mean sequence (Cu3), sandwiched between two Bragg mirrors at the fifth generation (Bg5). Our system realizes a polychromatic filter that transmits five wavelengths in the visible spectrum independently of the polarization of the light transverse electric or transverse magnetic. Secondly, the photonic crystal (Bg5/Cu3/Bg5) undergoes the deformation y = xk + 1 (where k is the degree of deformation, x and y are respectively the coordinates of the system before and after the deformation). With a proper choice of the degree of deformation k, this photonic crystal maintains its property of polychromatic filter whose transmission wavelength is independent of the polarization’s state. Thanks to this deformation, we can disperse the optical windows in different spectra of visible light and exactly in the violet, blue, green, and orange light. This system can be used in the fabrication of color filter devices and the white light emitting diodes.

5

Microwave properties of the generalized Fibonacci quasi-periodic multilayered photonic band gap structure

Trabelsi Y., Kanzari M., Rezig B.

Optica Applicata

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2009

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Vol. 39, nr 2

319-329

EN

The transmission properties in microwave domains (10 GHz to 40 GHz) of generalized dielectric Fibonacci multilayer generated by the rule Sl+1 = SmlSnl-1: with a pair of positive integers m and n were studied. The initial generations of generalized Fibonacci sequence are taken as follows: S0 = L and S1 = H, where H and L are two elementary layers with refractive indices nL = 1 (air) and nH = 3 (ceramic). The so-called "trace map method" was used to simulate the transmission spectra of the multilayer structures at normal incidence. Based on the representation of the transmittance spectra in the microwave range an analysis depending on the pair (n, m) is presented. It has been shown that the reflection bands of the proposed quasi-periodic structure could cover the whole spectral range. By comparison, it is impossible to reach this result by using the periodical multilayer structure.

6

Interferential polychromatic filters based on the quasi-periodic one-dimensional generalized multilayer Thue - Morse structures

Bouazzi Y., Kanzari M.

Optica Applicata

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2009

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Vol. 39, nr 3

489-498

EN

In this paper, a new type of optical filter using photonic band gap materials has been proposed. The optical filter was obtained by a combination of periodic H(LH)J and generalized Thue - Morse (GTM) quasi-periodic one-dimensional multilayer. We show that the whole structure H(LH)J[TM]PH(LH)J, where P is the repetition number of the GTM stack, has an interesting application as a polychromatic filter. However, the effect of the repetition number for producing an improved polychromatic filter is presented. So, switches like (on-on-off-off-on-on-…) have been found.