Third-order nonlinear optical response of Ag–CdSe/PVA hybrid nanocomposite

Abstract

Hybrid nanocomposites of II-VI semiconductor nanoparticles are gaining great interest in nonlinear optoelectronic devices. Present work includes the characterization of CdSe polymer nanocomposite prepared by chemical in situ technique. From X-ray diffraction, the hexagonal wurtzite structure of nanoparticles has been confirmed with spherical morphology from transmission electron microscopy. Ag-CdSe hybrid polymer nanocomposite has been prepared chemically at different Ag concentrations. The presence of Ag in hybrid nanocomposite has been confirmed with energy-dispersive X-ray spectroscopy. The effect of varying Ag concentration on the linear and nonlinear optical properties of the nanocomposites has been studied. In linear optical parameters, the linear absorption coefficient, refractive index, extinction coefficient and optical conductivity have been calculated. The third-order nonlinear optical properties have been observed with open-and closed-aperture Z-scan technique. The large nonlinear refractive index *10 -5 cm 2 /W with self-focusing behaviour is due to the combined effect of quantum confinement and thermo-optical effects. The enhanced nonlinearity with increasing Ag content is due to the surface plasmon resonance, which enhances the local electric field near the nanoparticle surface. Thus, Ag-CdSe hybrid polymer nanocomposite has favourable nonlinear optical properties for various optoelectronic applications.

Alteration of structural, optical and electrical properties of CdSe incorporated polyvinyl pyrrolidone nanocomposite for memory devices

“…Increased value of n 2 in case of nanocomposite samples in contrast with the pure polymer is due to the presence of nanoparticles in the polymer matrix as it is clearly seen in Table 4. Similar behavior is studied by Tripathi et al 72 for Ag-CdSe/PVA hybrid nanocomposites.…”

Nonlinear optical properties of metal nanoparticles: a review

“…Herein, the pure CdSe PNC was marked as sample A. Ag-CdSe hybrid PNC was prepared via a colloidal chemical synthesis technique by mixing the required amounts of Ag colloids with CdSe PNC. 108 The volume fraction of Ag was changed by keeping the volume of CdSe PNC constant. The prepared nanocomposite samples had the composition Ag(x)-CdSe PNC, with x ¼ 0.1, 0.2, and 0.3%, and these samples were marked as B, C, and D, respectively.…”

“…Values of the linear absorption coefficients (a) and nonlinear parameters extracted from the Z-scan measurements108 …”

Study on the Third-Order Nonlinear Optical Properties of Cd2+ Ion Doped Zns/PVP Nanocomposite FilmsB. Suresh1, S. Ramachandran1 and G. Shanmugam2

“…7(b). The closed aperture (CA) plot shows a valley to peak nature which exhibits strong self-focusing with positive nonlinear refraction [12][13][14][15][16]. The data were analysed using the procedures described by Sheik-Bahae et al [22].…”

“…In order to resolve it, different substrates were used for making ZnS thin films to extract the true values of nonlinear optical coefficients of ZnS nanoparticles [8][9][10][11]. In recent years, self standing nanocomposite films containing semiconducting nanoparticles embedded in polymer matrix have been widely attracted by many researchers due to the following factors: (a) mono-dispersion of nanoparticles can be easily achieved in polymer matrix, (b) true nonlinear optical coefficients of nanoparticles can be obtained, (c) easy preparation and estimation of nonlinear optical coefficients, (d) improved thermal and mechanical stabilities [12][13][14][15][16].…”