Polymer-based second harmonic generation materials are disclosed, including electric field poled, chromophore-functionalized polyphenylene ethers with second harmonic coefficients (d.sub.33) as high as 65.times.10.sup.-9 esu, Tg.apprxeq.173.degree. C., and with superior temporal stability of the poling-induced chromophore orientation. Procedures for simultaneously poling and diepoxide cross-linking chromophore-functionalized poly(.rho.-hydroxystyrene) are set forth, resulting in a significant improvement in the temporal stability of chromophore orientation. Chromophore immobilization is disclosed involving highly cross-linkable epoxy matrices. In a first procedure chromophore molecules are embedded in a matrix which can be simultaneously poled and thermally cured. In a second procedure, a functionalized high-.beta. chromophore is synthesized for use as an epoxy matrix component.
A method for producing a composite material, wherein compound A having a group selected from an aliphatic hydrocarbon group, aromatic hydrocarbon group and heterocycle-containing group which comprises a functional group which can bond to a compound B allowed to bond to a substrate, then compound B having a functional group which can bond to said functional group in compound A is allowed to bond to compound A is disclosed. Embodiments in which compound A is represented by formula (1); R.sup.1 M.sup.1 Y.sup.1.sub.3, formula (2); R.sup.1 R.sup.2 M.sup.1 Y.sup.1.sub.2, formula (3); R.sup.1 R.sup.2 R.sup.3 M.sup.1 Y.sup.1 and formula (4); R.sup.1 --SH: embodiments in which compound A is a silane compound: the functional group of compound A is a halogen group or an epoxy group: and embodiments in which compound B is selected from aliphatic hydrocarbon compounds, aromatic hydrocarbon compounds and heterocycle-containing compounds having an amino group, carboxyl group or hydroxyl group, are preferred.
The design and synthesis of a family of calix[4]arene-based nonlinear optical (NLO) chromophores are discussed. The calixarene chromophores are macrocyclic compounds consisting of four simple D-.pi.-A units bridged by methylene groups. These molecules were synthesized such that four D-.pi.-A units of the calix[4]arene were aligned along the same direction with the calixarene in a cone conformation. These nonlinear optical super-chromophores were subsequently fabricated into covalently bound self-assembled monolayers on the surfaces of fused silica and silicon. Spectroscopic second harmonic generation (SHG) measurements were carried out to determine the absolute value of the dominant element of the second-order nonlinear susceptibility, d.sub.33, and the average molecular alignment, .PSI.. A value of d.sub.33 =60 pm/V at a fundamental wavelength of 890 nm, and .PSI..about.36.degree. was found with respect to the surface normal.
The invention relates to a hydrophilic thin film and a method of manufacturing the same in which the hydrophilic thin film is formed by incorporating or fixing molecules comprising hydrophilic groups to a chemically adsorbed film on a substrate surface.
A new electro-optic (EO) phase modulator constructed from a combination of a low-loss passive polymer waveguide and a self-assembled chromophore superlattice (SAS) with an intrinsically polar microstructure. In contrast to typical polymer-based modulators, the present invention utilizes a siloxane SA methodology that enables the acentric alignment of constituent chromophores during film growth without the need for post-deposition electric field poling. The guiding layer is constructed of the SAS and the glassy polymer Cyclotene.TM.. The use of SiO.sub.2, Cytop.TM. and Cyclotene.TM. glassy polymers, results in a straightforward device fabrication process that is compatible with the thermally and photochemically robust SAS. Thus, nanoscale control of the film architecture results in greatly simplified macroscopic device fabrication. The present invention provides a SAS-based electro-optic modulator demonstrating excellent electro-optic response properties and a .pi. phase shift.
The present invention concerns an electrical junction between one transistor and at least one voltage sensitive cell such as a neuron. The invention further concerns transistors to be used in said junction and methods for their preparation. By another aspect the invention concerns "an artificial chemical synapse" i.e. a junction between a cell, which secretes an agent, and a transistor bearing receptors for the agent, wherein binding of the agent to the receptor changes an electrical property off the transistor.
