Optomechanical device for frequency doubling enhancement are described. The devices include a substrate through which light of a first wavelength is introduced, a first reflector mirror, a conductive layer disposed on the first reflector mirror, and a second mirror spaced apart from the conductive layer, thereby forming an optical cavity between the second mirror and the conductive layer. The devices also include a power source coupled to the second mirror and the conductive layer and a monolayer of non-linear optical material disposed within the optical cavity, the monolayer being configured to produce light of a second wavelength upon interaction with the light of the first wavelength. The second mirror is deformable upon introduction of voltage from the power source and deformation of the second mirror changes a length of the optical cavity, thereby enhancing a power output of the light of the second wavelength produced by the monolayer.

A nonlinear nanocomposite optical-element comprising a nanocomposite comprising one or more optically nonlinear (NLO) nanofillers dispersed in a cured organic-matrix. The NLO nanofillers have a high .sup.(3) susceptibility relative to a linear nanofiller. The distribution of the NLO nanofiller has a nanofiller gradient that changes based on optical radiation intensity.

A nonlinear nanocomposite optical-element comprising a nanocomposite comprising one or more optically nonlinear (NLO) nanofillers dispersed in a cured organic-matrix. The NLO nanofillers have a high .sup.(3) susceptibility relative to a linear nanofiller. The distribution of the NLO nanofiller has a nanofiller gradient that changes based on optical radiation intensity.

Problem to Be Solved: to provide a chromophore having a far superior nonlinear optical activity to conventional chromophores and to provide a nonlinear optical element comprising said chromophore.

Solution: a chromophore comprising a donor structure D, a -conjugated bridge structure B, and an acceptor structure A, the donor structure D comprising an aryl group substituted with a substituted oxy group; and a nonlinear optical element comprising said chromophore.

Organic charge-transfer (CT) co-crystals in a crossed stack system are disclosed. The co-crystals exhibit bidirectional charge transfer interactions where one donor molecule shares electrons with two different acceptors, one acceptor face-to-face and the other edge-to-face. The assembly and charge transfer interaction results in a pleochroic material whereby the optical absorption continuously changes depending on the polarization angle of incident light.

A compound is represented by Formula (1) below,

##STR00001##

in Formula (1) above, R.sup.1 to R.sup.22 each independently contain at least one atom selected from the group consisting of H, B, C, N, O, F, Si, P, S, Cl, I, and Br, and L.sup.1 and L.sup.2 each independently represent a single bond or CC.

Problem to Be Solved: to provide a chromophore having a far superior nonlinear optical activity to conventional chromophores and to provide a nonlinear optical element comprising said chromophore. Solution: a chromophore comprising a donor structure D, a -conjugated bridge structure B, and an acceptor structure A, the donor structure D comprising an aryl group substituted with a substituted oxy group; and a nonlinear optical element comprising said chromophore.

A method for the inscription of second-order nonlinear optical properties on a support including an amorphous material, the method including: heating the support within a temperature range allowing the movement of charges inside the support; applying a structured electrode to the support, generating an electrical field designed to induce the formation of non-linear optical properties on the surface of the support; and cooling the support.

The invention provides a composite polymer film material based on a tungsten/copper/sulfur cluster compound, a preparation method and use thereof. The cluster compound has a chemical formula of: [RWS.sub.3Cu.sub.2(L.sup.a)].sub.n(M).sub.n, wherein R is tris(3,5-dimethylpyrazolyl)hydroborate, tris(pyrazolyl)hydroborate, or pentamethylcyclopentadienyl; L.sup.a has a structural formula of:

##STR00001## when M is perrhenate, n is 4; and when M is triflate, n is 6. The synthesis process of the cluster compound is simple and controllable. A tetrahedral and an octahedral tungsten/copper/sulfur cluster compound that are good third-order nonlinear optical (NLO) active species are selectively synthesized by using different cuprous salts. Composite polymer films of various layers are prepared by spin coating. Such films, as flexible, portable and easy-to-process solid materials, are applicable to third-order NLO devices. With increasing layers in the film, the third-order NLO response is gradually enhanced, and is 3-4 orders of magnitude higher than a solution containing the cluster compound.

Nonlinear optical chromophores having one or more diamondoid groups covalently attached to the chromophore, methods of making nonlinear optical chromophores, their use in thin films and electro-optical devices containing such nonlinear optical chromophores and thin films comprising the same.