Rational design of organic electro-optic materials

Abstract

Quantum mechanical calculations are used to optimize the molecular first hyperpolarizability of organic chromophores and statistical mechanical calculations are used to optimize the translation of molecular hyperpolarizability to macroscopic electro-optic activity (to values of greater than 100 pm V −1 at telecommunications wavelengths). Macroscopic material architectures are implemented exploiting new concepts in nanoscale architectural engineering. Multi-chromophore-containing dendrimers and dendronized polymers not only permit optimization of electro-optic activity but also of auxiliary properties including optical loss (both absorption and scattering), thermal and photochemical stability and processability. New reactive ion etching and photolithographic techniques permit the fabrication of three-dimensional optical circuitry and the integration of that circuitry with semiconductor very-large-scale integration electronics and silica fibre optics. Electro-optic devices have been fabricated exploiting stripline, cascaded prism and microresonator device structures. Sub-1 V drive voltages and operational bandwidths of greater than 100 GHz have been demonstrated. Both single-and double-ring microresonators have been fabricated for applications such as active wavelength division multiplexing. Free spectral range values of 1 THz and per channel modulation bandwidths of 15 GHz have been realized permitting single-chip data rates of 500 Gb s −1 . Other demonstrated devices include phased array radar, optical gyroscopes, acoustic spectrum analysers, ultrafast analog/digital converters and ultrahigh bandwidth signal generators.

Structural, Electrical and Optical Characterization Studies on Glycine Picrate Single Crystal : A Third Order Nonlinear Optical Material

“…The variation of dielectric constant with frequency is shown in 4. The dielectric constant (ε') obtained for GP is higher at the lower frequencies and then it decreases with the increasing frequencies and saturates for further increase in the frequency which can be attributed to space charge polarization mechanism of molecular dipoles [17]. It is important to note that temperature has not influenced much on the dielectric behaviour of the GP crystal.…”

“…The electronic exchange of a number of ions in the crystals gives local displacement of electrons in the direction of the applied field, which in turn gives rise to polarization. Crystals with high dielectric constant lead to more power dissipation and hence at higher frequencies, the power dissipation in the crystal may have lower value [17]. …”

Theory and computations of two-photon absorbing photochromic chromophores

“…These properties originate in a highly polarizable π-electron system and find a wide use in organic electronics [78] and photonics [79] applications. Another reason for interest in electronically excited states of polyenes is their role in biological processes of vision and photosynthesis.…”

“…The -conjugation through the six-membered phenyl ring allows for partial transfer of the electron density from the donor to the acceptor groups in both the ground and excited states. This electron mobility results in a number of properties important for organic electronics [78] and photonics [79] applications.…”

Theoretical study on the mechanism of reaction between 3-hydroxy-3-methyl-2-butanone and malononitrile catalyzed by lithium ethoxide

“…In past years, chromophore-functionalized electrooptic (EO) polymeric materials have been iintensively investigated for their potential applications in highspeed photonic devices [1]. This has led to extensive explorations of 'push-pull' type chromophores with high molecular second-order nonlinearity.…”