Novel Thermally Stable Cross-Linked Nonlinear Optical Silica Films Prepared by a Sol−Gel Process

Abstract

To improve the orientational stability of the chromophore induced by an electric field in a second-order nonlinear optical polymer, we have synthesized a thermally stable and cross-linkable azo dye, 4-[(4‘‘-aminophenyl)sulfonyl]-4‘-[N,N-bis(2-hydroxyethyl)amino]azobenzene. The transparent films with silica as matrix and organic chromophore as cross-linking agent were then prepared by using a sol−gel process. The resulting films heated at 200 °C under a high-corona field exhibited the nonlinear optical coefficient d 33 = 32 pm/V in Maker-fringe measurement. Long-term stability of second-harmonic coefficients in these films was observed even at 160 °C.

Electric-field-induced layer-by-layer fabrication of inorganic–organic hybrid second-order nonlinear optical films

“…The d 33 value of a single bilayer film was found to be 47 pm V À1 , which is higher than that of the previously reported sol-gel film materials [72][73][74], due to the effect of electric field inducing during the deposition process. As shown in Fig.…”

Alcóxidos como precursores na síntese de novos materiais através do processo sol-gel

“…Os materiais com propriedades ópticas 51,52 , condutoras 53 ou catalíticas [54][55][56] foram também sintetizados, baseando-se sempre no uso de alcóxidos de silício como precursores. Quando se usou o TEOS em presença de moléculas modeladoras, tornou-se possível a obtenção de materiais com estruturas tubulares 57 .…”

Preparation and second-order optical nonlinearity of inorganic–organic hybrid films

“…Covalent linked hybrid inorganic-organic materials are commonly prepared by sol-gel process of the alkoxysilane dye which can be designed to bear a functional chromophore in one arm of silicon through a flexible spacer [12]. The resultant structure is similar to that of a side-chain polymer.…”