Effect of the Refractive Index of Nano-Particles on Intensity and Spectral Shift of the Fluorescence Emission from Dye/NP Colloidal Suspensions

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1 ,* *corresponding author -. 6G ,0.0 - PACS Effect of the Refractive Index of Nano-Particles on Intensity and Spectral Shift of the Fluorescence Emission from Dye/NP Colloidal Suspensions H. Kafian, P. Parvin, A. Bavali, M. Hashemi Nekoo, N. Seif Mazhari, Kamal Saberian Physics Department, Amirkabir university of technology: P.O. Box ,Tehran, Iran Nuclear Energy Organization, Tehran, Iran Abstract- Fluorescence emission of the colloidal suspension of various nanoparticles with the same size, shape and mass in rhodamine 6G ethanolic solution has been measured to investigate the effect of refractive index on the intensity and spectral shift. Both intensity changes and spectral shifts show differences for different refractive indices. Though the effect of this difference in low densities of nanoparticles is coincident with the Rayleigh scattering theory, this is not kept for high amount of the scatterers. Keywords: Refractive Index, Nano-Particle, Laser Induced Fluorescence, Rayleigh scattering PACS No: ,0.0

2 σ [3]. Rayleigh s n 5 π d = 4 3λ 6 n n + σ s λ σ s () d.. (() ) : I I ( + cos θ ) n -- [3] π 4 6 = ( ) ( ) 0 R λ n + () d n (). () (). : (quenching).(disaggregation). ( ) -....[,] (DLS) 6G. (localization). (random laser)

3 . [3]( ) -3 LIF : 6G ZnO (4) (3). 6G TiO ZnO SiO Al O ) 0 0/ ( C 8 H 3 N O 3 Cl) 6G C H 5 OH, ) ( MW=479.0 gr/mol %99. (Merck PH. METROHM. () PH PH 87PHLAB. 6G :3 TiO ZnO SiO Al O PH PH () TiO ZnO Al O 3 SiO 6G :4 TiO ZnO SiO Al O 3 Nd:YAG G 4/5 (cuvette). Ava-spec 048 (). 0/4. 3

4 ) ((3) ) () 5.( -5 6G... [] Sha, W. L, Liu, C. H, Liu, F, Alfano, R. R, Competition between two Lasing Modes of Sulforhodamine 640 in Highly Scattering Media, 77 9, Opt. Let, 996. [] A. M. Brito-Silva, A. Galembeck, A. L. Gomes, A. J. Jesus-Silva, C. B. Araújo, Random Laser Action in Dye Solutions Containing Stöber Silica Nanoparticles, J. Applied Physics, 08 (00) -5. [3] Diederik Sybolt Wiersma, LIGHT IN STRONGLY SCATTERING AND AMPLIFYING RANDOM MEDIA, Ph.D. thesis, University of Amesterdam, 995. [4] M. Mohammadian, P. Parvin, A. Bavali, M. R. Mousavipour, Effect of TiO Nanoparticles on the Spectral Characteristics of Rhodamine 6G Fluorescence Emission, Proceedings of the 4 th International Conference on Nanostructures (ICNS4) -4 March, 0, Kish Island, I.R. Iran [5] Shuzhen, F, Xingyu, Z, Qingpu, W, Chen, Z, Zhengping, W, Ruijun, L, Inflection Point of the Spectral Shifts of the Random Lasing in Dye Solution with TiO Nanoscatterers, 0505, J. Phys (3) (red shift) /8. ).(. (inflection point) ( ). ( ).[,3]. ( ). (4) (single scattering)" " multiple )" ". (scattering (). 4

5 * *corresponding author. (6G ). ).. (. ZnO ,0.0 PACS Effect of Solvent on Intensity and Spectral Shift of Laser Induced Fluorescence Spectroscopy of Nano-Particle Colloidal Rd6G Solution H. Kafian, P. Parvin, A. Bavali, M. Hashemi Nekoo, V. Daneshafrooz, Mojgan Falahati Physics Department, Amirkabir university of technology: P.O. Box ,Tehran, Iran Abstract- In this work, ethylene glycol and ethanol as solvents, are compared from the perspective of the effect of viscosity on fluorescence intensity and spectral shift in laser induced fluorescence spectroscopy of colloidal suspension of ZnO nanoparticles in Rd6G solution. Experimental measurements show that for ethylene glycol, the intensity of fluorescence spectrum is reduced because of higher viscosity and refractive index of the solvent. In addition, the emission peak experiences the red shift. Relative intensity curves of the two samples shows that there is a maximum intensity of the emission spectrum (inflection point) in which the experiments have better signal-to-noise ratio. Keywords: viscosity, ethanol, ethylene glycol, ZnO nanoparticles, laser induced fluorescence spectroscopy PACS No: ,0.0

6 K BT D = 3πaτ a τ. T D () [3] K B. ) ( 6G. (re-emission) (re-absorption) (self quenching).[5] (dynamic quenching).[4] -3 6G MW=479.0 %99 C 8 H 3 N O 3 Cl) (C H 5 OH, Merck) ((HOCH CH ) O, Merck) (gr/mol ) 0 ( Nd:YAG - 6G /5 Ava-spec (cuvette) 0/ / ).[,] ( (agglomeration). ( ) (sonicator) (ultrasonic bath) (diffusion) (Viscosity)

7 6G : ZnO ().. 6G :3 ZnO LIF :() 6G ZnO -4 () (inflection point) (). CH 3 CH OH (HOCH CH ) O (5 0 C) ( 0 C) -4-9 ( 0 C) () (3) () ZnO 6G... 3

8 [] Sha, W. L, Liu, C. H, Liu, F, Alfano, R. R, Competition between two Lasing Modes of Sulforhodamine 640 in Highly Scattering Media, 77 9, Opt. Let, 996. [] A. M. Brito-Silva, A. Galembeck, A. L. Gomes, A. J. Jesus-Silva, C. B. Araújo, Random Laser Action in Dye Solutions Containing Stöber Silica Nanoparticles, J. Applied Physics, 08 (00) -5. [3] K. Huang, Statistical mechanics (Wiley, New York, 963) [4] M. Mohammadian, P. Parvin, A. Bavali, M. R. Mousavipour, Effect of TiO Nanoparticles on the Spectral Characteristics of Rhodamine 6G Fluorescence Emission, Proceedings of the 4 th International Conference on Nanostructures (ICNS4) -4 March, 0, Kish Island, I.R. Iran [5] Shuzhen, F, Xingyu, Z, Qingpu, W, Chen, Z, Zhengping, W, Ruijun, L, Inflection Point of the Spectral Shifts of the Random Lasing in Dye Solution with TiO Nanoscatterers, 0505, J. Phys () [5]... (3).. () ) (.. (red shift).. -5 (6G ).. ( ). 4

9 بشسسی خ اص دی الکتشیکی کشیستال مایع( MBBA ) مخل ط شذ با واو رسات آ ه محمد حسيه مجلس آرا محمد صادق ذاكر حميدی علی ملکی آزمایشگا ف ت ويک داوشگا خ ارزمی تهران پصيهشکد عل م كاربردی ي ستار شىاسی داوشگا تبریس چکیده - ضشیب دی الکتشیک یک وم و کشیستال مایع وماتیک دس غلظت ای مختلف مخل ط شذ با واو رسات آ ه بش حسب دما دس فشکاوس 30KHz م سد بشسسی قشاس گشفت است. وتایج داد ای اوذاص گیشی شذ بیاوگش افضایش وا مساوگشدی بذلیل القای قطبش پزیشی واو رسات مغىاطیذ دس م لکل ل ای کشیستال مایع است. یک گشتايس ویشيی باصج گتگیشی ق ی بیه م لک ل ای کشیستال مایع با استفاد اص گشتايس دي قطبی پایذاس واو رسات ب ج د می آیذ. افضایش شذیذ ضشیب دی الکتشیک دس بل س مایع با افضيدن مقذاس واو رسات پتاوسل کاسبشد آو ا دس ومایشگش ای LCD بذلیل کا ش مقذاس اوشطی بکاس سفت ي پاسخ اپتیکی م لک ل ای کشیستال مایع سا بیش اص پیشتش وشان می د ذ. كد كليد ياش - كریستال مایع ضریب دی الکتریک واو ذرات فرريالکتریک آهه PACS Dielectric properties of a negative anisotropic liquid crystal sample doped with ferroelectric nanoparticle (Fe 3 O 4 ) M. H. Majles Ara, M. S. Zakerhamidi, Ali maleki ) Photonics Lab, Faculty of Science, Kharazmi University, Tehran, Iran ) Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz, Iran Abstract- The dielectric permittivity has been measured as a function of temperature at the frequency 30 KHz for different concentration of ferroelectric nanoparticle doped in nematic liquid crystal. Our measurements allowed us to suggest that increased anisotropy is caused by the contribution of polarizability anisotropy of the ferroelectric particles. Stronger reorientation torque is caused by the permanent dipole moment of the particles contributing to the dielectric anisotropy of the colloid. The enhancement of dielectric permittivity in LCs by doping with ferroelectric nanoparticles Fe 3 O 4 at extremely high concentration shows the strong potential of ferroelectric nanoparticles for improving the optical response of LCs and the low amount of energy used in an LCD displays. Keywords: Nematic liquid crystal, dielectric permittivity, nano particle PACS No:

10 Dielectric properties of a negative anisotropic liquid crystal sample doped with ferroelectric nanoparticle (Fe 3 O 4 ) Abstract: The dielectric permittivity has been measured as a function of temperature at the frequency 30 KHz for different concentration of ferroelectric nanoparticle doped in nematic liquid crystal. Our measurements allowed us to suggest that increased anisotropy is caused by the contribution of polarizability anisotropy of the ferroelectric particles. Stronger reorientation torque is caused by the permanent dipole moment of the particles contributing to the dielectric anisotropy of the colloid. The enhancement of dielectric permittivity in LCs by doping with ferroelectric nanoparticles Fe 3 O 4 at extremely high concentration shows the strong potential of ferroelectric nanoparticles for improving the optical response of LCs and the low amount of energy used in an LCD displays. Keywords: Nematic liquid crystal, nano particle, dielectric permittivity. relative to orientation of director), for which detailed theoretical calculations were obtained [4]. High anisotropy of the liquid crystal needs to decrease amount of energy used in an nematic liquid crystal display (LCD). There are two ways to go about this, first would be to create a new liquid crystal material that is very costly. The other more feasible way is to take some material that is known to have a higher dielectric anisotropy and mix it into the liquid crystal matrix. The following research was done using the ferroelectric nanoparticle doped liquid crystal. ). The following research was done using the ferroelectric nanoparticle Fe 3 O 4 and a nematic liquid crystal, MBBA in an attempt to increase the dielectric anisotropy of the liquid crystal cell. Introduction Suspensions of colloidal particles in liquid crystal samples is increasingly studied as a method to improve the physical and electro-optical properties of liquid crystals (LCs) due to their potential application on different subject areas such as photonics and biotechnology. The visible spectrum onto the boundary surfaces. Commonly used doping nanoparticles include ferroelectric nanoparticles, metallic nanoparticles, inorganic nanoparticles, and ferromagnetic nanoparticles []. In Refs [-3], was studied the influence of magnetic nanoparticles on the Fredericksz transitions under the action of either electric field or magnetic one or under the simultaneous action of these fields in ferronematics based on different LC. It should be noted that experimental investigations were carried out mainly for those conditions (orientation of molecules in a cell, orientation of the electric and magnetic field Experimental The liquid crystalline material N-(4-Methoxy benzylidene) -4-butylaniline (MBBA) (Fig a) was synthesized in the institute of chemistry of the Military Technical Academy, Warsaw, Poland. Cetyltrimethylammonium bromide (CTAB) (Fig b) was used as a surfactant. A surfactant was added to the solution containing nanoparticles to reduce the effect of aggregation of the nanoparticles. The surfactant adsorbs on the surface of the nanoparticles and minimizes cold welding between powder particles and thereby inhibits agglomeration. The desired situation is when CTAB just covers the entire surface of each nanoparticle with a monolayer. If the concentration of CTAB exceeds its optimal value, after mixing with liquid crystals the mixture will deteriorate the liquid crystal order. If, on the other hand, the concentration of oleic acid is lower than its optimal value, the nanoparticles are not completely coated and aggregate with time.

11 The real part of dielectric permittivity, Ɛ, has been measured for the temperature range of 8 to 50, for states that liquid crystal molecules have been parallel and perpendicular to the electric field direction. The temperature dependence of dielectric permittivity in both parallel and perpendicular direction for MBBA liquid crystal and different concentration of nanoparticle doped liquid crystal at frequencies 30 khz is shown in Fig. And at the other side, it shows that by adding nanoparticle, dielectric permittivity in both perpendicular and parallel direction increases sharply. And the phase transition point (clearing temperature) has been changed by doping nanoparticles in liquid crystal. (b) (c) Fig ) Chemical structure of a) MBBA, b) CTAB and c) the production sample To preparation our cells, The nematic samples were doped with a magnetic suspension that consists of nearly spherical Fe 3 O 4 magnetic particles coated with CTAB as a surfactant. The dielectric measurements have been performed by LCR meter having an accuracy of (Instek LCR-89). The sand-witched type of capacitance sample contained with an aligner layer of polymer; PVA for parallel and Lecithin for perpendicular aligned, is used for dielectric measurements. The dielectric measurements have been done in perpendicular and parallel direction. The values of capacitance of the sample were determined both in fill and without of liquid crystal. The change in capacitance value will give the value of real part of dielectric permittivity, after elimination effects of ITO layer and alignment polymer layer. 3 Results Fig ) Temperature dependence of different concentration of nanoparticle doped MBBA LC

12 Fig 3) model for the organization of NP doped LC a) % wt, b)5% wt, c)0% wt From Fig, it is obvious that the high concentration of nanoparticles (0% wt) containing higher dielectric constant than the other percentages. For investigating these phenomena, we have considered the mutual influence of spherical ferromagnetic nanoparticles and nematic LC molecules. There are two sources of coupling between a NP and its nematic surrounding: the magnetic coupling and elastic coupling [5]. Characteristically each of them is dominated in various concentrations. Considering superparamagnetism, at low consentration % wt, suspensions of colloidal particles in liquid crystal samples have been caused by a strong dipole-dipole interaction between the super-paramgnetic particles and the surrounding liquid crystal molecules (see Fig 3.a). In this circumstance, the LC matrix orientates nanoparticles in the direction of long molecular direction and alternatively, the orientational interaction of LC molecules with nanoparticles give rise to leading a strong tracing of the particle orientation director. The mediocre ordering of nanoparticles and LC as a function of increasing concentration of NPs in the absence of external fields, schematically showed in Fig 3.b. As seen, the nematic ordering gradually decreases with the adding NP concentration and make a large static disorder into the LC molecules. In reality the size of magnetic particles is considerably larger than the dimensions of the lc molecules, inasmuch as the magnetic particles can be considered as macroscopic objects floating in the LC. Consequently the surface of the dispersed colloidal particles plays crucial role in disrupting of the adjacent LC molecules ordering. Anchoring of LC molecules on the polar group of CTAB molecules induces long range orientation distortions via dispersion and Van der Waals interactions. To minimize these distortions, the particles act like a radial hedgehog so tends to formation of linear aggregate in agreement with theoretical considerations [6]. At high concentration because of anchoring of surfactant molecular with the aligned layer (PVA) of the cell and also hyperbolic hedgehog effect, the elastic forces generate. As schematically plotted in Fig 3.c, these forces caused the particles aggregates as a chain-like (rod-like) form. Subsequently, the surfactant molecules locally orients the Nematic LC matrix perpendicular to the surface of chainlike nanoparticles during the transition from isotropic liquid to nematic phase consequently make a high dielectric constant. 4 Conclusion Using CTAB as a surfactant has been reduced the effect of aggregation of the nanoparticles. And the experimental results of the measuring temperature dependence of dielectric permittivity has been showed that use of the ferroelectric nanoparticle suspended in a liquid crystal matrix shows a significant increase in the dielectric anisotropy of the liquid crystal cell by adding nanoparticles concentration because of the strong dipole-dipole interactions. References [] G. Barbero, Phys. Rev. E 65(3), 0370(00). [] P. Kopčanský,M. Koneracká, V. Zavisova et, J. Phys. IV (Paris)7, p (997). [3] O. Buluy, E. Ouskova, Yu. Reznikov et al., Magn. Mater.5, p (00). [4] H. Atkuri, G. Cook, D.R.Evans, hetnyak, J. Opt. A: Pure Appl. Opt (5pp) (009) [5] F. Brochard and P. G. de Gennes, J. Phys. (Paris) 3, 69 (970). [6] B. I. Lev, S. B. Chernyshuk, P. M. Tomchuck, and H. Yo-koyama,Phys. Rev. E65, 0709 (00) 4

13 انذازه گیری غیرخطیت اپتیکی نانو ررات مخلوط شذه در بلور مایع با استفاده از روش جاروب Z محمد حسيه مجلس آرا محمد صادق ذاكر حميدی علی ملکی آزمایشگا ف ت ويک داوشگا خ ارزمی تهران پصيهشکد عل م كاربردی ي ستار شىاسی داوشگا تبریس چکیذه کشیستال ىای مایع م ادی ىستنذ کو تیشتش تخاطش اکنش ىا خ اص اپتیکی غیش خطی تسیاس تاال مشي س ىستنذ. یژگی ىای غیش خطی تل س ىای مایع تا افض دن نان رسات مغناطیسی تو ص ست قاتل ت جيی افضایش می یاتنذ. دس مقالو حاضش مقذاس جزب خطی دامنو عالمت ضشیة شکست غیش خطی تشای غلظت ىای مختلف نان رسات مخل ط شذه تا تل س مایع تا استفاده اص تکنیک قذست منذ جاس ب س ی مح س Z م سد یشسسی قشاس گشفتو است. انذاصه گیشی ىا تا استفاده اص لیضس پی ستاس He-Ne تا ط ل م ج 8..6 انجام گشفتو انذ. كد كليد ياش - كریستال مایع تکىيک جاريب Z-scan واو ذرات ) 4 (Fe 3 O PACS Z-Scan measurements of optical nonlinearities of the ferroelectric nanoparticle doped liquid crystal M. H. Majles Ara, M. S. Zakerhamidi, Ali maleki ) Photonics Lab, Faculty of Science, Kharazmi University, Tehran, Iran ) Research Institute for Applied Physics and Astronomy, University of Tabriz, Tabriz, Iran Abstract- : Nematic liquid crystal (NLC) is a material that features a large nonlinear optical response. The nonlinearity can be enhanced by doping a nanoparticle into a nematic liquid crystal host. In this paper, we investigated the linear absorption, amplitude and the sign of the nonlinear refractive indices for various concentrations of ferroelectric nanoparticles (Fe 3 O 4 ) doped in nematic liquid crystal by using the z-scan technique. The measurements were performed using a CW He:Ne laser tuned at 63.8 nm. Keywords: Nematic liquid crystal, Z-scan technique, nanoparticle (Fe 3 O 4 ) PACS No:90.090

14 Z-Scan measurements of optical nonlinearities of the ferroelectric nanoparticle doped liquid crystal Abstract: Nematic liquid crystal (NLC) is a material that features a large nonlinear optical response. The nonlinearity can be enhanced by doping a nanoparticle into a nematic liquid crystal host. In this paper, we investigated the linear absorption, amplitude and the sign of the nonlinear refractive indices for various concentrations of ferroelectric nanoparticles (Fe3O 4 ) doped in nematic liquid crystal by using the z-scan technique. The measurements were performed using a CW He:Ne laser tuned at 63.8 nm.. Keywords: Nematic liquid crystal, nano particle, Z-scan technics. Introduction In linear optical processes the physical properties of the liquid crystal, such as molecular structure, individual or collective molecular orientation, temperature, density, and population of electronic levels are not affected by the optical fields. However the direction, amplitude, intensity, and phase of the optical-fields are affected in a unidirectional way. Liquid crystals are optically highly nonlinear materials and their physical properties i.e. temperature, molecular orientation, density and electronic structure can be easily perturbed by applied optical-field []. Since liquid crystalline molecules are anisotropic hence a polarized light from a laser source can induce an alignment or order in the isotropic phase, or realign the molecules in the ordered phase. The optical properties of liquid crystals can be controlled by external applied DC or lowfrequency fields; which gives rise to a variety of electro-optical effects which are widely used in many electro-optical display and image-processing applications. There are several methods for nonlinear characterization of materials such as z- scan which is a powerful technique to obtain both the sign and magnitude of the complex nonlinear refractive index of some optical materials. This technique is based on the principle that spatial variations of the incident intensity distribution can photoinduce a lens in the nonlinear material which affects the posterior propagation of the beam and intensity changes at the far-field. Liquid crystalline suspensions of various micro- or nanoparticles have recently been the subject of renewed interest. because they combine the fluidity and anisotropy of liquid crystals with the specific properties of the particles []. In particular, ferroelectric nanoparticles, being doped into liquid crystals at very low concentrations, introduce a number of effects [4] At this work, we investigated the amplitude and the sign of the nonlinear refractive indices for various concentrations of ferroelectric nanoparticles (Fe3O 4 ) doped in nematic liquid crystal by using the z-scan technique. Experimental The liquid crystalline material (w-680) was synthesized in the institute of chemistry of the Military Technical Academy, Warsaw, Poland For our experiments we have chosen one of the most studied ferroelectrics Fe 3 O 4. These small particles ( 0 nm) would finally aggregate together and fall out because of attractive vander Waals forces. In the case of ferroelectric particles there will be additional electrostatic forces. Therefore, in order to prevent agglomeration and segregation, the particles must be coated with a

15 monomolecular film of a dispersing agent that prevents agglomeration. For this mean, Cetyltrimethylammonium bromide (CTAB) was used as a surfactant. Then the mixture was doped in liquid crystal sample (Fig ). In the z-scan technique, the laser beam is focused using a lens and the sample is translated along the beam axis (z-axis) through the focal region over a distance several times that of the diffraction length. The light intensities, transmitted across the samples, were measured as a function of the sample position in the z-direction with respect to the focal plane either through a small aperture (closed aperture) or without an aperture (open aperture), in order to resolve the nonlinear refraction and absorption coefficients. The z-scan experimental set-up for the CW laser is shown schematically in Fig.. The samples were moved along the optical axis (z-direction) through the focal plane of the lens with 80 mm focal length. A CW He Ne laser at 63.8 nm was used as the light source and the laser beam waist set at the focal point, the radius of the waist of the illumination beam inside the sample was 5mm. An aperture was fixed at the distance of 00 cm from the focal temperature) has been changed by doping nanoparticles in liquid crystal. The close-aperture (CA) curve was obtained after division of CA data with the open-aperture (OA) data to eliminate the contribution of nonlinear absorption and is shown in figure. The difference between normalized peak and valley transmittance T p_v (denoting T p -T v ) can be directly measured by z-scan technique. The nonlinear refractive index n (cm /w) can be obtained from : The peak-to-valley configuration of the CA/OA z- scan curve for Fe 3 O 4 nanoparticles doped liquid plane (closed-aperture scheme) Fig ) The z-scan experimental apparatus is recorded as a function of the sample position Z. crystal reveals a self-focusing effect, and the refractive index has a negative sign. 3 Results We calculate the linear absorption α by measuring output power with a sample as a function of the power without the sample in low powers. The experimental result of optical limiting behaviour of NLCs pure and with deferent concentration of nanoparticle doped LC at λ= 63.8 nm. The linear absorption is related to the scope of line in Fig. and obtains from below equation:

16 Figure : Z-scan data of Fe 3 O 4 nanoparticle doped liquid crystal with a closed-aperture 4 Conclusion The peak followed by a valley-normalized transmittance curve obtained from the closed aperture Z-scan data, indicates that the sign of the refraction nonlinearity is negative, i.e. self-defocusing. The self-defocusing effect is due to the local variation of the refractive index with temperature. The exprerimental results has been shown that adding nanoparticle in liquid crystal give rise to increase of nonlinearity in LC material. So that the highest mount of nonlinearity ocures for % wt. References [] I.C. Khoo, Phys. Rev. A. 3 (98) 077 [] Brochard F and de Gennes P G 970J. Physique369 [3] Reznikov Yu, Buluy O, Tereshchenko O, Glushchenko A and West J 005 SPIE Int. Soc. Opt. Eng.5747 [4] M. H. Majles ara, Z. Dehghani, Journal of Modern Physics: ConferenceSeries Vol (0) 4

17 ... BK , PACS Measurement of Nonlinear Optical Responses of Ag Thin Films Adeleh Granmayeh Rad, Hamed Abbasi. Roudehen Branch, Islamic Azad University, Roudehen, Iran. Department of Photonics, Faculty of Physics, University of Kashan, Kashan, Iran Abstract- In this paper we report the preparation of silver nanoparticle thin films by cylindrical direct current reactive magnetron sputtering (at 0-5 torr initial pressure) and characterization of their nonlinear optical properties. BK7 glasses were selected as substrate. Nonlinear optical response of silver nanoparticle thin films was measured by moiré deflectometry technique using 5 mw He-Ne laser illuminations. All fabricated silver nanoparticle thin films were evaluated using atomic force microscopy and spectrophotometry (from visible region to near infrared region). Keywords: Silver thin film, DC magnetron sputtering, Moiré deflectometry, Nonlinear refractive index. PACS No: ,

18 (n).[7] n = n0 + ni = n0+ n. n (cm W - ) : I (W cm - ) n (n ) () n I = I 0 ω 0 r exp ω ( z) ω ( z). z ω(z) n 0.. : ω 0 () n = n I 0 ω 0 r exp ω ( z) ω ( z ) : (3) n,min θf πω = 4z dp 4 0 in z0 α t min : d ) α min ) n,min (4) CCD (. ( z t p in. tp z t = λ f. : (5) -.. ).[] (......[3].[]. -.[4] [5] 0..[6].

19 t λ p. : n min θf = z ω0 tdz0 α min n min (6).. 7 : : CCD torr BK (Unico uv-00).. : 7 :4. (AFM) Scientific Park).(Instruments, Auto Probe cp 7...(Dektak 3 Profilometer) 3

20 : [] A. Granmayeh Rad, H. Abbasi, Preparation of Colloidal Silver Nanoparticles by Laser Ablation; Evaluation and Study on its Developed Applications, Adv. Mater. Res. 488/489 (0) 409. [] M. Sheik-Bahae, A.A. Said, T.W. Wei, D.J. Hagan, E.W. Van Stryland, Sensitive Measurement of Optical Nonlinearities Using a Single Beam, IEEE J. Quantum Electron 6 (990) 760. [3] M. H. Majles Ara, E. Koushki, S. H. Mousavi, S. Salmani, M. Rafizadeh, A. Gharibi, Nonlinear optical properties of a dithiooxamide determined by single beam techniques, Mater. Chem. and Phys. 09 (008) 30. [4] I. Glatt, O. Kafri, Moire Deflectometry Ray Tracing Interferometry, Opt. Lasers Eng. 8 (988) 77. [5] K. Jamshidi-Ghaleh, N. Mansour, Nonlinear refraction measurements of materials using the moire deflectometry, Opt. Commun. 34 (004) 49. [6] S. Rasolui, K. Jamshidi-Ghaleh, Erratum to Nonlinear refraction measurements of materials using the moiré deflectometry, Opt. Commun. 84 (0) 48. [7] Kh. Madanipour, N. Taheri, A. Granmayeh Rad, H. R. Zangeneh, Experimental and theoretical study of nonlinear interaction effects in laser and nanoparticles by Moiré deflectometry, Proceeding of 7th Photonics Conference of Iran. : cm W - α min d=7 nm BK7 4

21 روگ تر کائ له غلظت اثر تررسی ي پ دری لعاب تا سرامیک گ و ای سیستماتیک ت لیذ آن ومهذیشفیعیآفارانی مجیذرشیذیهویه علیمحمذمصباحینیا دانشکذهیعلوم دانشگاهسیستانوبلوچستان زاهذان کذپستی گروهفیسیک گروهمهنذسیمواد دانشکذهیمهنذسیشهیذنیکبخت دانشگاهسیستانوبلوچستان زاهذان کذپستی ت سط ایران در دیرتاز از ساخت فرایىذ در فلسی اکسیذ ای او اع حض ر از واضی خرم ر ت معريف سىتی سرامیک گ و ای چکیذ میتاضذ. خرم ر سیلیسی تذو در فلسی اکسیذ ای وف ر از واضی سرامیک ا گ و ایه دلفریة روگ است. میضذ ت لیذ ایراوی صىعتگران استفاد کائ له پرکىىذ ی ماد ی ي سذیم ي کلسیم کرتىات ای ي مس اکسیذ سیلیس از وم و ا سیستماتیک ت لیذ ترای پصي ص ایه در عکس ای ضذوذ. پخت الکتریکی ک ر ی یک در ي گرفت قرار پ دری لعاب درين سپس ي ضذوذ ساخت سیلیسی تذو ای وخست گردیذ. مچىیه است. سرامیک ا گ و ایه در مس اکسیذ واو متری ررات يج د وطاند ىذ ی ت لیذی وم و ای لعاب سطح از گرفت ضذ استفاد تا آو ا روگ پایان در گرفت. قرار مطالع م رد تازتاب طیف در تغییرات ي لعاب روگ مس اکسیذ ررات اوذاز ی تر کائ له غلظت تأثیر مییاتذ. افسایص ویس روگ غلظت پ دری لعاب در کائ له غلظت افسایص تا مید ذ وطان وتایج گردیذ. تعییه روگسىجی ريش از SEM روگسىجی. کائ له مس اکسیذ واو ررات پ دری لعاب خرم ر ياش - کلیذ 606 کذ PACS Systematic Fabrication of a Kind of Ceramic Using Powder Glazing Method and Study of Kaolin Concentration on its Color Alimohammad Mesbahinia, Majid Rashidi-Huyeh and Mahdi Shafiee Afarani School of Physics, Faculty of Sciences, University of Sistan & Baluchestan, Zahedan, Iran School of Materials Engineering, Faculty of Engineering, University of Sistan & Baluchestan, Zahedan, Iran Abstract- A traditional ceramics, known as Khar-mohre, have been fabricated by Iranian craftsmen. The attractive color of such ceramics is due to metal oxide diffusion in Khar-mohre silica body. In this communication, for systematic fabrication of samples, silica, copper oxides, carbonates and kaolin, as an filler, were used as starting materials. Then silica bodies were formed and imbedded in powder glaze and fired in an electric furnace. SEM micrographs of samples show the presence of nanoparticles of copper oxide. The effect of Kaolin Concentration on Copper Oxide Nanoparticle Size, glaze color and changes in the reflection spectrum also was studied. Finally their colors were determined using the colorimetric method. The results show that the color of glaze become more concentrated by increasing of kaolin in glaze powder. Keywords: Khar-mohre, powder glaze, Copper oxide nanoparticles, Kaolin, Colorimetric method.