Nonlinear optical properties DFT calculations of polyacethylene and copolymers models substituted with aldimines chromophores as side chains

Aldimine derivatives chromophores grafted on polyacetylene oligomers were first designed to investigate the nonlinear optical (NLO) response of the resulting materials using CAMB3LYP method. The effects of different factors such as the chain length separating the substitutions as well as the configurations and the orientations of these latter, were examined and discussed. In a second part of this paper, NLO responses, in particular the static hyperpolarizabilities of polyvinyl oligomers substituted by aldimine chromophores via carboxylic groups and by pyrrolidone groups were calculated for different configurations. The stability and the hydrogen bonding in each oligomer were also discussed.

Efficiently poled electro-optic polymer modulators

A titanium dioxide (TiO₂) / electro-optic (EO) polymer hybrid waveguide modulator was designed and fabricated. This modulator possessed a significant advantage for realizing high poling efficiency regardless of the EO polymer resistivity. The in-device EO coefficient was measured to be 100 pm/V, which was 32% higher than that of the thin polymer film. As a result, the phase modulator displayed a VπL figure of merit of 3.5 V∙cm at 1550 nm, which can be reduced further in a push-pull Mach-Zehnder interferometer structure. Temporal stability test of the modulator at 85°C indicated only 8% change of Vπ over 500 hours. The propagation loss in the waveguide was measured as ~3 dB/cm.

Synthesis and characterization of electro-optic polyurethane-imide and fabrication of optical waveguide device

The novel electro-optic (EO) polymers of fluorinated cross-linkable Y-type polyurethane-imides (PUI) were designed and synthesized by polycondensation of second-order non-linear optical azo-based chromophores, phenyl diisocyanate, and aromatic dianhydride. Molecular structural characterization for the resulting polymers was achieved by proton nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, elemental analysis, and gel permeation chromatography. The resulting polymers exhibited good film-forming properties, high glass transition temperature in the range from 186°C to 198°C and thermal stability up to 300°C, high EO coefficient ( γ33 = 43–60 pm/V) at 1550 nm wavelength, good stabilization of electrically induced chromophore dipole alignment and low optical propagation losses in the range of 1.5–1.7 dB/cm at 1550 nm, which are suitable for the EO modulators. Using the synthesized EO PUI as the active core material and of a fluorinated polyimide as cladding material, we have designed and fabricated the high-performance polymer waveguide Mach-Zehnder EO modulators. Obvious modulation was observed by application of ac voltage signal to the EO modulators.

Research of the optimum molar ratio between guest and host chromophores in binary chromophore systems for excellent electro-optic activity

A series of binary chromophore systems were designed and prepared. The optimum molar ratio (OMR) between guest and host chromophores was first systematically explored in the BCSs. When at the OMR, there is the biggest EO coefficient growth rate.

Functional hyperbranched polymers with advanced optical, electrical and magnetic properties

This review summarizes the recent progress in functional HBPs and their application in optics, electronics and magnetics, including light-emitting devices, aggregation-induced emission materials, nonlinear optical materials, chemosensors, solar cells, magnetic materials, etc., and provides outlooks for further exploration in the field.

High refractive index polyvinylsulfide materials prepared by selective radical mono-addition thiol–yne chemistry

Linear and hyperbranched polyvinylsulfides with a high refractive index (n_D = 1.68–1.76) have been synthesized by selective mono-addition thiol–yne chemistry employing dithiols and di- and trialkynes.