Order Nonlinear Optical Polymers Research Articles

Design and preparation of novel diazo chromophores with flexible isolated groups

Novel nonlinear optical chromophore with strong electron donor, diazo electron bridge and isolation groups on both sides were synthesized and characterized by mass spectrum and hydrogen nuclear magnetic resonance. Strong electron donor and diazo electron bridge improve the nonlinear optical activities of the chromophore, large and reactive isolated groups improve the chromophore’s solubility and reduced the interaction among the chromophores. Second order nonlinear optical polymers with different chromophore loading densities were prepared and showed us the smallest glass transition temperature change. Large second order nonlinear optical coefficients were also gotten by second harmonic generation method 15.3, 27.2 and 33.4 pm/V for chromophore loading density at 10, 22.5 and 27.5 wt% respectively.

“H”-shape second order NLO polymers: synthesis and characterization

In this work, two "H"-shape and one "AB"-type second order nonlinear optical (NLO) polymers were prepared for the first time. The linkage positions of chromophores in the "H"-shape polymers were shoulder-to-shoulder, in which the chromophore moieties were part of the polymeric backbone. The subtle structure could be easily modified by the introduction of different isolation groups, to adjust the property of the resultant polymers. All the polymers exhibited good film-forming ability and thermal stability. The second harmonic generation (SHG) experiments demonstrated that the two "H"-shape polymers (P1 and P2) exhibited large SHG coefficients of d(33) values (up to 90 pm V(-1)), and P2 even demonstrated relatively good long-term temporal stability.

Design and fabrication of segmented, slotted waveguides for electro-optic modulation

Recently, slotted waveguides have been used in conjunction with second order nonlinear optical polymers to provide a platform for electro-optic modulation at telecommunication frequencies. A challenge with these devices is the need to provide high-frequency electrical driving signals to the slots. The silicon resistivity must be high to reduce optical loss, and as a result electrical performance can be severely limited. We have designed and fabricated a class of waveguide that achieves quasicontinuous electrical contact with subwavelength segmentations and has low optical losses of 4dB∕cm, allowing both millimeter-wave and optical fields to be concentrated in the same area.

The Sense of Chromophore Orientation in Films Made by Alternating Polyelectrolyte Deposition

Abstract : Alternating polyelectrolyte deposition (APD) is a technique for fabricating multilayer thin films at room temperature. The substrate is alternately dipped in two different aqueous solutions - one containing a polycation and the other a polyanion. By incorporating chromophores in the polycation and/or polyanion, it has been demonstrated that the APD process can be used to make multilayer second order nonlinear optical polymer films. In addition, a recent encouraging discovery is that these films exhibit a high degree of thermal robustness.

THE SYNTHESIS, CHARACTERIZATION, AND PHOTOCHEMICAL CROSSLINKING OF AN NLO EPOXY POLYMER

A photocrosslinkable second order nonlinear optical (NLO) epoxy polymer, Bisphenol A-Nitroaminotolane, containing covalently attached cinnamate side chain substituents (BisA-NAT-CM), was synthesized. After corona poling Second Harmonic Generation (SHG) is used to measure the relaxation of the anisotropy after the electric field is removed. Upon photolysis at 260 nm the cinnamoyl side chains undergo photochemical dimerization to crosslink the NLO polymer. Photobleaching is not a problem under these conditions. The photocrosslinked NLO polymer shows virtually no relaxation over a period of 500 hours at room temperature and good temporal stability at temperatures as high as 110°C.

Synthesis and Poling of A Crosslinked Second Order Nonlinear Optical Polymer with Liquid Crystalline Side Groups

Synthesis and Poling of A Crosslinked Second Order Nonlinear Optical Polymer with Liquid Crystalline Side Groups

Orientaion and Relaxation in a Polyisocyanate-Crosslinked Second Order Nonlinear Optical Polymer

Orientaion and Relaxation in a Polyisocyanate-Crosslinked Second Order Nonlinear Optical Polymer

Orientaion and Relaxation in a Polyisocyanate-Crosslinked Second Order Nonlinear Optical Polymer

Orientaion and Relaxation in a Polyisocyanate-Crosslinked Second Order Nonlinear Optical Polymer

Synthesis and characterisation of crosslinked second order nonlinear optical polymer

The present paper reports the synthesis of glycidyl monoether of 4-[(p-nitrophenyl) azo] phenol (GMNA) and crosslinking reaction of GMNA with hexamethylene diisocyanate biuret (HDIB). The Tg of crosslinked polymer was investigated by DSC. The orientation and stability of the poled and crosslinked polymer film were studied by UV-Vis spectra and Maker fringe method.

Design of new polydiacetylenes as self assembling second order nonlinear optical polymers

Abstract

Channel Waveguides and Modulators Fabricated From High Temperature Second Order Nonlinear Optical Polymers

ABSTRACTBuried channel wave guides have been fabricated from thermally stable non linear optical polyimides. The Material system consists of a polyimide cladding and a polyimide based active Material. The buried channel wave guides are fabricated by a trench and fill process. This process was used for the fabrication of active wave guides at process temperatures above 300 °C. Single Mode wave guides, and Mach-Zenhder interferometers, were fabricated with attenuation < 2 dB/cm. Active Mach-Zehnder interferometers with a Vπ phase shift of 50 volts and the low attenuation were fabricated. Thermal aging of the poled active device demonstrated no change in activity after 30 Minutes at 230°C.

Demonstration of Dispersive Optical Bistability With a Third Order Nonlinear Optically Active Polymer

ABSTRACTDispersive optical bistability in a Fabry-Perot (F-P) cavity with a third order nonlinear optical polymer was demonstrated. This effort involved the development of several nonlinear optical polyimides and an evaluation of their linear optical and nonlinear optical properties. These Materials were processed into waveguiding films having good homogeniety and optical properties. Several of these films were shown to have desirable third order nonlinearities, while exhibiting good mechanical and environmental stability. Characterization of these materials involved the measurement of their absorption profiles, film thicknesses, optical waveguide propagation constants and nonlinear optical susceptibilities. Based on the measured results, a specific polyimide was chosen and used to demonstrate an all-optical instrinsic bistable device operating at a wavelength of 1.06 μ. Using ∼ 100 ps input pulse widths at 1.06 μ, dispersive optical bistability originating from the induced refractive index change, δn, due to an electronic nonlinearity of the polyimide was observed.

Synthesis, Characterization, and Processing of Organic Nlo Polymers

ABSTRACTThe research described in part in this manuscript is a multi disciplinary effort to target key applications and material and processing requirements for these third order nonlinear optical polymers. It discusses the synthesis, characterization, and processing of nonlinear optical properties of polyimides which have been tailored for nonlinear optical activity.

Linear and Non-Linear Optical Properties of (2-Cyano-5-Methoxy-1,4-Phenylenevinylene) and Paraphenylenevinylene Copolymers

ABSTRACTPoly(CMPV-co-PV) have been synthesized via water soluble sulfonium salt precursor route and their linear and non-linear optical properties were characterized. The electro-optic response was stable up to 100°C when the materials were poled during the elimination. The thermal stability and mechanical strength of PPV and its derivatives, and easy processibility from the precursor polymers suggest a new approach for the molecular design of the 2nd order non-linear optical polymers.

New polymers with large and stable second-order nonlinear optical effects

Second order nonlinear optical (NLO) polymers containing NLO moieties with large optical nonlinearities and a cross-linkable unit have been synthesized using difunctionalized disperse red dye. The enhanced second order NLO coefficients, X exp (2) of 250 pm/v for the first polymer and 500 pm/v for the second, were obtained at 532 nm using the corona poling method. The introduction of flexible chains into the polymer backbone is found to cause a decrease in glass transition temperature and, hence, a decrease in the stability of the second-order NLO effects.

Polymers for Nonlinear Optical Applications

Abstract Since the 1987 Brookhaven Symposium on Electroresponsive Molecular and Polymer Systems, the materials research targets that electro-optical and nonlinear optical (NLO) polymers must achieve for device and systems application have become better defined. The progress of second and third order NLO polymer development toward achieving these goals is reviewed. In particular polymer design is being guided by new concepts which have been predicted from theory and validated by experiment.

Molecular Design of Stable Second Order Nonlinear Optical Polymers

ABSTRACTThe temporal and thermal stability of second order nonlinear optical properties of polymers is an important issue in the development of poly meric electro-optic devices. This has been addressed by introducing interchain crosslinking. A number of crosslinked systems developed by photochemical reactions have been presented.

Photocross-Linked Second Order Nonlinear Optical Polymers

ABSTRACTWe report a novel method to obtain stable second order nonlinear optical (NLO) properties in polymeric thin films. Photocross-linking between the NLO active molecules and a photoreactive polymer is achieved by UV irradiation subsequent to poling. The thin film exhibits a nonlinear coefficient d33of 16.5 pm/V at a doping level of 20% by weight of NLO active molecules and possesses quite stable second order nonlinear optical properties

Non-Linear Optical Polymers for Active Optical Devices

Second order non-linear optical (NLO) polymers have been the focus of intense research effort in recent years [1]. This effort is justified by the potential value of these materials in a range of attractive optical signal processing applications with lower device costs and enhanced device performance.