The present report explores third order nonlinear optical behavior of phase pure Yb3+:YAG nanoparticles for the first time by Z-scan technique. The measurement was carried out using diode pumped continuous wave (CW) Nd:YAG laser at 532 nm. The Yb:YAG nanoparticles exhibit characteristic near-infrared (NIR) emission at 1030 nm under 940 nm excitation. The nanoparticles exhibit high nonlinear refractive index (n2 = 8.649 × 10−8 cm2/W) and low nonlinear absorption coefficient (β = 0.109 × 10−4 cm/W) giving an appreciable figure of merit (FOM) of ∼74.50. The excitation power (8.2–10.5 W cm−2) dependent emission spectra were recorded to study exchange energy interaction of Yb3+ ions with YAG host lattice. By utilizing the nonlinear refractive index ‘n2’ from Z-scan measurement, thermo-optic coefficient (dn/dt) was calculated to demonstrate Yb3+:YAG nanomaterial for high power compact solid state laser gain amplifier systems. © 2018 Elsevier Ltd

Arun Kumar S

Department of Information Security

School of Computer Science and Engineering

Vellore Campus

Vinitha G

Physics

School of Advanced Sciences

Chennai Campus

Senthilselvan J

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Optics & Laser Technology

BaWO4 nanostructures doped with different concentrations of Yttrium have been synthesized by a chemical method. The as-prepared samples were characterized by UV–vis diffuse reflectance spectra, X-ray diffraction, Fourier transform infrared spectroscopy, Transmission electron microscopy and Raman spectra. From the UV–vis spectra, it is seen that absorption band edge shifted towards the visible region upon Y doping. The X-ray diffraction and Raman analyses reveal that the BaWO4 powders present a tetragonal structure. The third-order nonlinear optical responses of BaWO4 nanostructures on the effect of Y concentrations was investigated by Z-scan technique using a continuous wave Nd:YAG laser at 532 nm. Experimental results have shown that the observed nonlinear absorption and nonlinear refraction behavior is attributed to saturable absorption and thermal nonlinear effects. © 2018 Elsevier B.V.

Optical Materials

Spectral and third order nonlinear optical properties of Yttrium-doped BaWO4 nanostructures

By simple hydrothermal method, nanorods of barium boate were successfully loaded on reduced graphene oxide sheets. Powder XRD confirms the incorporation of barium borate (2θ = 29°, (202)) along with the transition of graphene oxide (2θ = 12°, (001)) into reduced graphene oxide (2θ = 25°, (002)). In the FTIR spectra, presence of characteristic absorption peaks of rGO (1572 and 2928 cm−1) and barium borate (510, 760 and 856 cm−1) further evidences the formation of BBO:rGO nanocomposite. FESEM images potray the existence of graphene sheets as thin layers and growth of barium borate as nanorods on the sheets of reduced graphene oxide. Ground state absorption studies reveal the hypsochromic shift in the absorption maxima of the graphene layers due to reduction of graphene oxide and hypochromic shift in the absorbance intensity due to the inclusion of highly transparent barium bortae. The photoluminescence of BBO:rGO shows maximum emission in the UV region arising from the direct transitions involving the valence band and conduction band in the band gap region. Z-scan technique using CW diode pumped Nd:YAG laser (532 nm, 50 mW) exposes that both nanocomposite and individual counterpart possess saturable absorption and self-defocusing behavior. Third-order nonlinear optical coefficients of BBO:rGO nanocomposite is found to be higher than bare graphene oxide. In particular the nonlinear refractive index of nanocomposite is almost four times higher than GO which resulted in superior optical power limiting action. Strong nonlinear refraction (self-defocusing) and lower onset limiting thershold makes the BBO:rGO nanocomposite preferable candidate for laser safety devices. © 2017 Elsevier B.V.

Barium borate nanorod decorated reduced graphene oxide for optical power limiting applications

A new organic nonlinear optical material, imidazolium diphenylacetate diphenylacetic acid, with excellent structural characterization and nonlinear optical activity has been reported.

New Journal of Chemistry

Crystal structure, molecular packing, FMO, NBO, nonlinear optical and optical limiting properties of an organic imidazolium diphenylacetate diphenylacetic acid single crystal

Thermal lensing and two photon absorption with saturable absorption based optical limiting behaviour in Co: ZnO nanoparticles under CW and pulsed Nd: YAG laser irradiation.

Journal	Data powered by TypesetOptics & Laser Technology
Publisher	Data powered by TypesetElsevier BV
ISSN	0030-3992
Open Access	No