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Theoretical guidance based on correlated real-time, time-dependent density functional theory (RTTDDFT) quantum mechanical and pseudo-atomistic Monte Carlo molecular dynamical (PAMCMD) statistical mechanical computational methods have led to dramatic (exceeding a Moore’s rate) improvement in molecular and macroscopic optical nonlinearity. New materials permit optical signal processing at terahertz rates using millivolts electrical and milliwatt optical control powers. Theory has also provided insight into the optimization of optical loss, thermal stability, and photochemical stability. The advent of silicon photonics for telecommunication applications has raised the prospect of achieving high density integration of photonic circuitry and even the chipscale integration of photonics and electronics. Such integration promises significant improvement in size, weight, and power (SWAP) together with dramatic improvements in performance, cost, and reliability. We demonstrate the integration of organic nonlinear optical materials into 25–150 × 200 nm slots in silicon photonic ring microresonator and stripline device structures. Slotted waveguides permit nearly lossless transition of light from 450 × 200 nm silicon photonic waveguides into the organic nonlinear optical material filled slots for active control of light. These device structures permit dramatic enhancement of electrical and optical control fields amplifying the already large nonlinearities of organic pi electron materials. Such amplification permits observation of new phenomena such as low optical power optical rectification, difference frequency generation, and all-optical signal processing.

In order to explore the effects of incorporation of an amino-phenyl-thienyl (APT) donor moiety into state-of-the art donor-bridge-acceptor organic NLO chromophores, two new materials were synthesized and characterized. Density functional theory (DFT) quantum-mechanical modeling indicates that this structural modification, producing enhanced ground-state electron density asymmetry and increased conjugation length, should lead to appreciable enhancement in first molecular hyperpolarizability ( β ). Previous empirical data suggests that such an approach to enhancements in nonlinearity may overcome the tradeoffs in nonlinearity with optical absorption and thermal stability, often encountered in organic NLO chromophore design. Material properties were evaluated in terms of poling-induced electro-optic coefficients normalized against applied poling field ( r 33 / E p ), DFT calculated β and gas-phase dipole moment, experimentally determined β HRS , absorption maxima, and thermal stability. These data were then compared against those from benchmark materials. Experimental data were determined to reflect enhancements in nonlinearity with little detriment to thermal stability and optical absorption, making them excellent candidates for use in electro-optic polymer applications. The most active material (C3) demonstrated highly reproducible values of r 33 = 130 pm/V.