An Alternative Route Based on Acid−Base Hydrolytic Chemistry to NLO Active Organic−Inorganic Hybrid Materials for Second-Order Nonlinear Optics

Abstract

An alternative approach, based on simple acid−base hydrolytic chemistry, to prepare organic−inorganic composites is reported. In these hybrid materials, NLO-active chromophores such as Disperse Red 19, a pyridinium salt based dye, and 1-amino-4-nitrobenzene are covalently locked into silica networks. The resulting hybrids are soluble and offer ease of processibility in the preparation of good-optical-quality thin films. Network materials that are akin to the traditional sol−gel approach are also prepared from the monofunctional NLO chromophore DR1 and, as expected, are found to be insoluble. Physical properties of the NLO chromophore-incorporated hybrids can be tailored by changing the molar amounts of chromophores and water, and the type of chromophore. High thermal stability and glass-transition temperatures of these hybrids offer effective electric-field poling at high temperatures and long-term temporal stabilities of the second-harmonic-generation signals at room temperature and at 80 °C. The χ(2) values for the networks were found to be in the range of (1.2−37) × 10-8 esu.

Development and characterisation of integrated microfluidics on waveguide-based photonic platforms fabricated from hybrid materials

“…Compared to pure organic polymers, sol-gel processed hybrid materials have advantages linked not only to their superior tunability as outlined above, but also linked to the production of interpenetrating, covalently bonded organic and inorganic networks within a single material, permitting the synthesis of materials with unique combinations of properties. Furthermore, the presence of a strong and rigid inorganic network formed through the hydrolysis and condensation reactions of the hybrid precursors confers superior long-term thermal stability compared to purely organic polymer materials (Zhang et al 2004;Jiang and Kakkar 1999;Buso et al 2009). This high degree of tunability offers the potential to satisfy a diverse range of material requirements.…”

Azo Chromophore Monomerically Bonded Mesostructured Silica Films with Large Third-Order Nonlinearity but Negligible Nonlinear Absorption

“…The NLO of azobenzene chromophore physically and/or chemically loaded in organic and inorganic polymeric matrices has been widely studied. 1,[21][22][23][24][25][26][27][28] Nevertheless, as mentioned above, few samples satisfy the figures of merit for alloptical applications even with large nonlinearity.…”

Effect of thermal treatment on the nonlinear optical response and stability of hybrid inorganic–organic films

“…Among them, hybrid inorganic-organic materials, prepared through sol-gel processing, are considered promising materials mainly because of the inherent properties of the silica matrix [8][9][10][11]. In addition, thin films of the inorganic silicon network can avoid or greatly reduce surface damage induced by corona discharge poling, which is a serious problem in poled polymer based thin films [12].…”