@article{MuzikanteFonavsTokmakovetal.2005,
  author    = {Muzikante, I. and Fonavs, E. and Tokmakov, A. and Cepite, D. and Stiller, Burkhard and Brehmer, Ludwig and Neilands, O.},
  title     = {Optical and electrical properties of oriented thin films of oligomer containing betaine-type moiety in side chain},
  issn      = {0370-1972},
  year      = {2005},
  abstract  = {Non-linear optical and electrical properties of polymer films obtained by dipole orientation of active units are reported. Novel polar oligomer with N-(indan-1,3-dion-2-yl)pyridinium betaine (IPB) as a side group is studied. Orientation of polar groups in oligomer thin films causes an increase of the photo-induced change of surface potential on irradiation in the region of photo-induced electron transfer (PIET) where the IPB group exhibits a reversible change of the value and sign of the dipole moment. At longer wavelengths, the value of the surface potential of the oligomer may be determined by transport of photo-generated charge carriers},
  language  = {en}
}
@article{KietzkeStillerLandfesteretal.2005,
  author    = {Kietzke, Thomas and Stiller, Burkhard and Landfester, Katharina and Montenegro, Rivelino V. D. and Neher, Dieter},
  title     = {Probing the local optical properties of layers prepared from polymer nanoparticles},
  issn      = {0379-6779},
  year      = {2005},
  abstract  = {It is well known that the performance of solar cells based on a blend of hole-accepting and electron-accepting conjugated polymers as the active material depend crucially on the length scale of the resulting phase separated morphology. However, a direct control of this morphology is difficult if the layer is prepared from an organic solvent. To circumvent this difficulty, recently a universal method to fabricate defined nano-structured blend layer using nanoparticles dispersed in water was demonstrated. These nanoparticles were prepared with the miniemulsion method, which allows for the preparation of semiconducting polymer nanospheres (SPNs) with diameters in the range of 30 to 300 nanometres. Since the process starts from the active material dissolved in a common solvent, it can be applied to the fabrication of nanoparticles of blends of polymers with oligomers or even with inorganic materials. We present here for the first time scanning near field optical microscopy (SNOM) investigations on these novel nanostructured polymer layers. We show that by spin-coating a mixture of two different dispersions a nanoparticle monolayer with a statistically distribution of the nanoparticles can be obtained. Mixing conjugated polymer nanoparticles with some inert particles like polystyrene beads may allow for the preparation of nano-sized light emitters},
  language  = {en}
}
@article{KarageorgievNeherSchulzetal.2005,
  author    = {Karageorgiev, Peter and Neher, Dieter and Schulz, Burkhard and Stiller, Burkhard and Pietsch, Ullrich and Giersig, Michael and Brehmer, Ludwig},
  title     = {From anisotropic photo-fluidity towards nanomanipulation in the optical near-field},
  issn      = {1476-1122},
  year      = {2005},
  abstract  = {An increase in random molecular vibrations of a solid owing to heating above the melting point leads to a decrease in its long-range order and a loss of structural symmetry. Therefore conventional liquids are isotropic media. Here we report on a light-induced isothermal transition of a polymer film from an isotropic solid to an anisotropic liquid state in which the degree of mechanical anisotropy can be controlled by light. Whereas during irradiation by circular polarized light the film behaves as an isotropic viscoelastic fluid, it shows considerable fluidity only in the direction parallel to the light field vector under linear polarized light. The fluidization phenomenon is related to photoinduced motion of azobenzene-functionalized molecular units, which can be effectively activated only when their transition dipole moments are oriented close to the direction of the light polarization. We also describe here how the photofluidization allows nanoscopic elements of matter to be precisely manipulated},
  language  = {en}
}
@article{HegewaldSchmidtGohsetal.2005,
  author    = {Hegewald, J. and Schmidt, T. and Gohs, U. and Gunther, M. and Reichelt, R. and Stiller, Burkhard and Arndt, K. F.},
  title     = {Electron beam irradiation of poly(vinyl methyl ether) films : 1. Synthesis and film topography},
  issn      = {0743-7463},
  year      = {2005},
  abstract  = {Temperature-sensitive hydrogel layers on silicon (Si) substrates were synthesized by electron beam irradiation of spin-coated poly(vinyl methyl ether) (PVME) films. The influences of the used solvent, the polymer concentration, and the spinning velocity on the homogeneity and the thickness of the PVME film were investigated. In the range of concentration c(p) = 1-15 wt\% PVME in ethanol solution, homogeneous films with a thickness between d = 50 nm and 1.7 mu m were obtained. The films were cross-linked by electron beam irradiation under inert atmosphere and analyzed by sol-gel- analysis. The results were compared with bulkgels formed by electron beam irradiation of PVME in the dry state. The film topography was analyzed by high-resolution field emission scanning electron microscopy and atomic force microscopy. An islandlike structure in the dry, swollen, and shrunken state of the hydrogel films was observed},
  language  = {en}
}
@article{DimitrievSmertenkoStilleretal.2005,
  author    = {Dimitriev, O. P. and Smertenko, P. S. and Stiller, Burkhard and Brehmer, Ludwig},
  title     = {Polyaniline-transition metal salt complexes: insight into formation mechanisms},
  issn      = {0379-6779},
  year      = {2005},
  abstract  = {Two basic morphologies of emeraldine base of polyaniline-transition metal salt complex films cast from N- methylpyrrolidinone solutions are described. The first morphology consists of grains and the other consists of loose aggregates, respectively. The correlation of the film morphology with formation of precipitate in the complex solution, kinetics of solvent evaporation from the cast film, amount of solvent entrapped in the film, film conductivity, and IR absorption spectra is shown. Two different mechanisms of the complex formation as a result of competition in the polymer- inorganic salt-solvent trio interactions are discussed; the first mechanism results in folding of macromolecules into compact coils being then a core of grains in the complex films, and the second mechanism leads to blending of the polymer chains with solvent giving rise to formation of loose aggregates. (c) 2005 Elsevier B.V. All rights reserved},
  language  = {en}
}
@book{MuzikanteFonavsBrehmeretal.2005,
  author    = {Muzikante, I. and Fonavs, E. and Brehmer, Ludwig and Stiller, Burkhard},
  title     = {Photoinuced phenomena in corona poled polar organic films},
  year      = {2005},
  abstract  = {Organic materials have received considerable attention because of their large dipole moments and optical nonlinearities. The optically induced switching of material properties is important for studying the optoelectronic effects including second harmonic generation. Organic materials for photonic applications contain chromophore dipole which consist of acceptor and donor groups bridged by a delocalized pi-electron system. Both theoretical and experimental data show a reversible highly dipolar photoinduced intra molecular charge transfer in betaine type molecules accompanied by change of the sign and the value of the dipole moment. The arrangement of polar molecules in films is studied both by atom force microscopy and surface potential measurements. To understand the photo response of these materials, their spectroscopic and electrical properties are studied. The morphology and photoinduced surface potential switching of the self-assembled monolayers and polymer films are investigated. (c) 2005 Elsevier B.V. All rights reserved},
  language  = {en}
}
@article{YinSchubertStilleretal.2008,
  author    = {Yin, Chunhong and Schubert, Marcel and Stiller, Burkhard and Castellani, Mauro and Neher, Dieter and Kumke, Michael Uwe and H{\"o}rhold, Hans-Heinrich},
  title     = {Tuning of the excited-state properties and photovoltaic performance in PPV-based polymer blends},
  doi       = {10.1021/Jp803977k},
  year      = {2008},
  language  = {en}
}