scholarly journals MEASUREMENT OF NONLINEAR RESPONSES AND OPTICAL LIMITING BEHAVIOR OF TIO2/PS NANO-COMPOSITE BY SINGLE BEAM TECHNIQUE WITH DIFFERENT INCIDENT INTENSITIES

2012 ◽  
Vol 05 ◽  
pp. 277-283 ◽  
Author(s):  
M. H. MAJLES ARA ◽  
Z. DEHGHANI

Titanium dioxide (titania) is a cheap, nontoxic and highly efficient photocatalyst being extensively applied for the degradation of organic pollutants, air purification, water splitting, reduction of nitrogen to ammonia, and optical devices due to its optical behaviors. The third-order nonlinear optical properties of TiO 2/ PS nano-composite were studied by means of single beam transmission technique, using a continuous-wave (CW) He - Ne laser beam with a wavelength of 632.8 nm with three different incident intensities. The magnitude and sign of the third-order nonlinear refractive index ( n 2) and nonlinear absorption (β) of TiO 2/ PS nano-composite were determined by use of both the closed-aperture and opened-aperture z -scan techniques. Z -scan technique, developed by Sheik-Bahae et al., has been used widely in material characterization. A single-beam (also called z -scan method) for measuring the sign and magnitude of nonlinear refraction that has simplicity and very high sensitivity has been reported recently. Optical limiting property of TiO 2/ PS nano-composite is studied. The positive sign obtained for nonlinear refractive index indicated that there is a self-focusing effect in the sample. The nonlinear refractive index was in order of 10-8 (cm2/W) and the nonlinear absorption coefficient was obtained in order of 10-2 (cm/W) with negative sign. The values of nonlinear refractive index and nonlinear absorption coefficient are enhanced by decreasing the intensity.

2020 ◽  
Vol 38 (3A) ◽  
pp. 440-445
Author(s):  
Zahraa M. AL-Asady ◽  
Ali H. AL-Hamdani

In this research, the diffraction ring patterns scan and single-beam Z-scan techniques were used to measure the nonlinear refractive index (n2) and nonlinear absorption coefficient (β). Nano-composite sample, which consists of zinc oxide nanoparticles (ZnO-NPs), and epoxy resin polymer. The sample was prepared by the casting method. A second harmonic generation Nd: YAG laser, which operates at 532 nm and intensity 3183 W/cm2 was used for the two techniques. Z-scan results showed that values for nonlinear refractive index n2 and nonlinear absorption coefficient β were obtained of 6.59*10-9 cm2/W and 1.75*10-3 cm/W respectively. While results for the D-scan technique showed that the number of rings increases with the increasing of laser power.


2011 ◽  
Vol 20 (02) ◽  
pp. 183-191 ◽  
Author(s):  
FRYAD Z. HENARI ◽  
ABDULLAH M. ASIRI

We report results from investigations of the nonlinear refractive index and nonlinear absorption coefficient of (2E)-3-[4-(Dimethylamino)phenyl]-1-(2,5-dimethylthiophen-3-yl)prop-2-en-1-one and (2E)-3-(3,4-Dimethoxyphenyl)-1-(2,5-dimethylthiophen-3-yl) prop-2-en-1-one using Z-scan technique with a continuous wave (cw) laser at wavelengths 488 nm and 514 nm. The nonlinear refractive index and nonlinear absorption coefficient of both samples were evaluated. The origin of the nonlinear effects was discussed. Optical limiting based on light induced nonlinear refractive index variation is demonstrated. The limiting thresholds were estimated for both samples. The results suggested that these materials offer promise as candidates for optical limiting and optical devices in the low power regime.


2009 ◽  
Vol 18 (04) ◽  
pp. 583-589 ◽  
Author(s):  
YUNDONG ZHANG ◽  
LEI MA ◽  
CHAOBO YANG ◽  
PING YUAN

The nonlinear-optical and optical limiting properties of 2(3), 9(10), 16(17), 23(24) phenoxy-phthalocyanines have been investigated using a 10-ns-pulse laser at 532 nm. The nonlinear absorption coefficient (β) is measured by the single beam Z-scan technique. We have observed low power optical limiting, with low limiting thresholds, based on nonlinear absorption in the sample. These studies indicate that the phthalocyanine material is a potential candidate for low power optical limiting applications.


2021 ◽  
pp. 1-7
Author(s):  
Bassam Abbas ◽  
Mohammad Alshikh Khalil

The Z-scan technique was employed to explore the third-order nonlinear optical properties of disperse red 13 organic chromophore solutions in tetrahydrofuran. A continuous-wave He–Ne laser (632.8 nm) was used as a source of irradiation. The nonlinear absorption and nonlinear refractive index coefficients of this dye were investigated. The results showed that this dye has a good nonlinear response with its real and imaginary quantities of third-order susceptibility. The solutions showed negative nonlinear refraction. The best obtained value of the third-order susceptibility was 6.37 × 10–3 esu at a dye concentration of 3.15 × 10–4 mol/L. Moreover, the nonlinear optical properties were enhanced with higher dye concentrations, and an elevated trend in nonlinear absorption and nonlinear refractive index coefficients was observed. Also, it was found that the reverse saturable absorption was the main mechanism responsible for the two-photon absorption effect in DSR13/THF samples.


2020 ◽  
Author(s):  
David Moss

We experimentally characterize the third-order optical Kerr nonlinearity of BiOBr nanoflakes via Z-Scan technique.Strong nonlinear absorption as well as high Kerr nonlinearity (n2) are observed at both 800 nm and 1550 nm, with alarge nonlinear absorption coefficient on the order of 10-7 m/W and a high Kerr coefficient on the order of 10-14 m2/Wbeing measured.


2016 ◽  
Vol 78 (3) ◽  
Author(s):  
Haider Mohammed Shanshool ◽  
Muhammad Yahaya ◽  
Wan Mahmood Mat Yunus ◽  
Ibtisam Yahya Abdullah

The study of nonlinear optical properties of polymer nanocomposites has been given increasing attention due its application in laser, communication and data storage technology. There is a need to enhance the understanding of all photonics technologies. In the current work, PMMA-ZnO nanocomposites as foils and as thin films have been successfully prepared. Casting method and spin coating were used to prepare them respectively. Nanocomposites were prepared by mixing ZnO nanoparticles with polymethyl methacrylate (PMMA) as the polymer matrix. Different contents of ZnO nanoparticles were used as the filler in the nanocomposites. The absorbance spectra of the samples were obtained. The linear absorption coefficient was calculated. The nonlinear refractive index and nonlinear absorption coefficient were investigated using a single beam Z-scan technique. A Q-switched Nd-YAG pulsed laser   (532 nm, 7 ns, 5 Hz) was used as a light source. Both thin film’s and foil’s samples showed peak absorption at 375 nm and increasing absorption with ZnO nanoparticles concentration. The nonlinear refractive index was in the order of 10-11 cm2/W for thin film samples and 10-12 cm2 /W for foil’s samples with a negative sign. In contrast, the nonlinear absorption coefficient is in the order of 10-6 cm/W and 10-7 cm /W for thin film and foil respectively. The figures of merit W and T were calculated in order to evaluate the suitability of the samples as optical switching device .However; they unsatisfied the requirements of optical switching devices but they can be considered as an excellent candidate for optical limiting.


2019 ◽  
Vol 23 (07n08) ◽  
pp. 701-717 ◽  
Author(s):  
Nobuhle Ndebele ◽  
Zweli Hlatshwayo ◽  
Bokolombe P. Ngoy ◽  
Gugu Kubheka ◽  
John Mack ◽  
...  

The results of recent studies on the optical limiting properties of BODIPY dyes at 532 and 1064 nm are described and compared. The optical limiting properties of novel 1,7-dimethyl-3,5-di-4-dihydroxyborylstyryl- and 3,5,7-tristyryl-1-methyl-BODIPY dyes were studied in CH2Cl2 and C6H6 and polystyrene thin films using the open aperture Z-scan technique at 532 nm with nanosecond laser pulses to provide an example of how the effective nonlinear absorption coefficient, the third order susceptibility, hyperpolarizability and limiting thresholds can be calculated.


2007 ◽  
Vol 21 (27) ◽  
pp. 1869-1877 ◽  
Author(s):  
QUSAY MOHAMMED ALI HASSAN

Investigation of nonlinear absorption coefficient of eosin blue dye based side chain poly(methacrylate) films is presented using diode pumped Nd:YAG laser radiation (λ=532 nm ) and the Z-scan technique. The effect of the concentration in polymer film and the increase in the number of methylene spacers, hooked to the eosin blue dye, on the nonlinear absorption coefficient is also discussed. It is shown that the nonlinear absorption coefficient in samples is due to the two-photon absorption effect. Moreover, the optical limiting characteristics of polymers film are explored.


Optik ◽  
2021 ◽  
Vol 227 ◽  
pp. 165975
Author(s):  
Yasemin Pepe ◽  
Ahmet Karatay ◽  
Yusuf Osman Donar ◽  
Elif Akhuseyin Yildiz ◽  
Ali Sınağ ◽  
...  

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