New Optical Nonlinear Material Based Upon PVA with PbS Quantum Dots

Nonlinear Optical Properties of PbS Nanocrystals Grown in Polymer Solutions

“…2,3 PbS nanocrystals have been previously synthesized by many methods and tested for their third order nonlinear optical properties, but different synthetic techniques can lead to different nanocrystal surface properties. These methods include standard surfactant based colloidal methods 4,5 as well as growth of the nanocrystals in matrices such as glasses, 6,7 polymers, 8,9 glues, 10 and zeolites. 11 Procedures for synthesizing lead sulfide nanocrystals in the presence of conjugated polymers have been developed where a sulfur precursor is injected into a degassed solution containing solvent, a lead precursor, and a polymer.…”

“…Nonlinear optical properties have been reported for only a few of the PbS nanocrystal materials prepared by these various synthetic techniques. 8,9 Nonlinear optical properties in semiconductor nanocrystals have been postulated to arise from a variety of physical mechanisms. When they are excited by photons with energy greater than the band gap energy of the nanocrystal, free carrier absorption, trapped state absorption, and multiphoton absorption are thought to be the underlying physical mechanisms behind nonlinear absorption.…”

Dip-coated PbS/PVP nanocomposite films with tunable band gap

“…Conjugated polymer hosts include poly[2methoxy-5-(2 0 -ethylhexyloxy-p-phenylenevinylene)] (MEH-PPV), [2][3][4][5][6][7][8] poly(2-(6-cyano-6 0 -methyl heptyloxy)-1,4-phenylene) (CN-PPP), 2 poly(3-hexylthiophene-2,5-diyl) (P3HT), 4,9-12 polypyrrole (PPy), 13 and poly[2-methoxy-5-(3 0 ,7 0 -dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV). 14 Insulating polymers, such as, polyacryl amide (PAM), 15,16 poly-p-xylylene (PPX), 17 polyacrylonitrile (PAN), 18 poly(methyl methacrylate) (PMMA), 19 polystyrene (PSt), 7,20,21 poly thiourethane (PTU), 22 polyvinyl alcohol (PVA), [23][24][25][26][27][28] poly(vinyl acetate) (PVAc), 29 poly(vinyl pyrrolidone) (PVP), 30,31 polyvinylidene uoride (PVDF), 32 and poly(ethylene oxide) (PEO) 33 have been employed as hosts. Films of PbS/conjugated polymer NCs have been basically investigated as a photoactive component of bulk heterojunction solar cells, 6,10,12,14,32,34 and photo detectors.…”

“…Films of PbS/conjugated polymer NCs have been basically investigated as a photoactive component of bulk heterojunction solar cells, 6,10,12,14,32,34 and photo detectors. Application of PbS/insulated polymer NC lms as photo-detectors, 3,20,27 high refractive index material, 22 non-linear optical device, 19,23,29 have been also explored. However, studies on interaction between PbS NPs and host polymer or control of band gaps of PbS NPs by polymer matrix are very few.…”

Effects of Surface Chemistry on Nonlinear Absorption of PbS Nanocrystals

“…Lead sulfide (PbS) nanocrystals are quantum-confined, group IV−VI, semiconductors which have shown great potential as nonlinear optical materials. − There are many synthetic pathways to PbS nanocomposites: standard surfactant-based nanocrystal growth methods; − growth of nanocrystals in glasses, , polymers, , glues, and zeolites; and by vacuum deposition methods. , These different lead sulfide materials can be made to exhibit both saturable, − ,, and reverse saturable absorption, ,,,, depending on the preparation method and laser parameters used.…”