Electro-optic single-crystalline organic waveguides and nanowires grown from the melt

Abstract

Organic nonlinear optical materials have proven to possess high and extremely fast nonlinearities compared to conventional inorganic crystals, allowing for sub-1-V driving voltages and modulation bandwidths of over 100 GHz. Compared to more widely studied poled electro-optic polymers, organic electro-optic crystals exhibit orders of magnitude better thermal and photochemical stability. The lack of available structuring techniques for organic crystals has been the major drawback for exploring their potential for photonic structures. Here we present a new approach to fabricate high-quality electro-optic single crystal waveguides and nanowires of configurationally locked polyene DAT2 (2-(3-(2-(4-dimethylaminophenyl)vinyl)-5,5-dimethylcyclohex-2-enylidene)malononitrile). The high-index-contrast waveguides (delta(n) = 0.54 +/- 0.04) are grown from the melt between two anodically bonded borosilicate glass wafers, which are structured and equipped with electrodes prior to bonding. Electro-optic phase modulation is demonstrated for the first time in the non-centrosymmetric DAT2 single crystalline channel waveguides at a wavelength of 1.55 microm. We also show that this technique in combination with DAT2 material allows for the fabrication of single-crystalline nanostructures inside large-area devices with crystal thicknesses below 30 nm and lengths of above 7 mm.

Synthesis, crystal growth, thermal and spectroscopic studies of acentric materials constructed from aminopyridines and 4-nitrophenol

“…During last years, organic nonlinear optical materials with high second-order nonlinear susceptibilities has found some applications in electro-optical devices such as optical waveguides or frequency modulators [1]. Three classes of electro-optical (EO) materials are used today: inorganic crystals (e.g., LiNbO 3 ), polymers or dendrimers doped with electro-optical dye molecules, and organic crystals with large EO coefficients [2,3].…”

The influence of pyrrole linked to the π-conjugated polyene on crystal characteristics and polymorphism

“…These measurements show that the pyrrole-based chromophores having asymmetric pyrrole easily form many polymorphs. On the other hand, for MM1 crystals having a symmetric dimethylaminophenyl electron donor we only observed one crystal structure, which was obtained by various methods, e.g., by solution growth method [16,22] with slow evaporation, rapid cooling, and slow cooling in various solvents such as methanol, ethanol, acetone, methylene chloride and acetonitrile, by melt [16,23] and vapor growth [24], as well as in DSC thermodiagram measurement.…”

Organic Single‐Crystalline Semiconductors for Light‐Emitting Applications: Recent Advances and Developments

“…Figi et al have utilized melt-recrystallization, in which the liquid of the melted organic material flowed into predefined channels by capillary force and crystallized upon cooling. [161][162][163] This method can give rise to the fabrication of high-quality electrooptic organic single-crystalline devices, such as optical waveguides, phase modulators, and microring resonators. After that, the melt-recrystallization method was applied to various conjugated semiconductor oligomers such as p-nP (n = 4-6), anthracene, BP1T, and AC5.…”

“…Figi et al. have utilized melt‐recrystallization, in which the liquid of the melted organic material flowed into predefined channels by capillary force and crystallized upon cooling . This method can give rise to the fabrication of high‐quality electrooptic organic single‐crystalline devices, such as optical waveguides, phase modulators, and microring resonators.…”