Publications by authors named "A Samoc"

Self-sustained all-optical poling second-harmonic generation (SHG) experiments are conducted in single-core and multicore dye-doped poly(methyl methacrylate) optical fibers. By tuning the polarization of the fundamental beam, the SHG signal is degraded and is reconstructed spontaneously up to its initial level. We found a new situation in which the photo-induced self-organization of azo polymers creates a well-ordered periodic structure.

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We present experimental studies of all-optical poling (AOP) in large-core dye-doped poly(methyl methacrylate) plastic optical fibers. We show that the confinement of light within the fiber core permits us to reach the upper limit of second harmonic generation achievable by AOP using repeated trans-cis isomerization. Quantification of the output power indicates self-seeding that can counteract relaxation of the orientation during readout of the induced nonlinearity.

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We describe a series of nine new complex salts in which electron-rich Ru(II) or Fe(II) centers are connected via pi-conjugated bridges to six electron-accepting N-methyl-/N-arylpyridinium groups. This work builds upon our previous preliminary studies (Coe , B. J.

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Triphenylamine derivatives bridged by methylene units afford a near planar molecular platform in a series of one dimer and two oligomers exhibiting increased structural rigidity compared to that of their parent triphenylamines. This series of dendrimers show significantly enhanced two-photon absorptions that are up to 3-fold that of triphenylamines with similar molecular size and structure.

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Poly(indenofluorene) shows a strong degenerate four-wave mixing (DFWM) response when it is excited with 100-fs pulses at 800 nm. The DFWM signal scales with the 1.5 power of the input intensity, which we interpret as being due to absorption saturation phenomena.

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