@article{HennebergRochonPanzneretal.2004,
  author    = {Henneberg, Oliver and Rochon, Paul and Panzner, Tobias and Finkelstein, Kenneth D. and Geue, Thomas and Saphiannikova, Marina and Pietsch, Ullrich},
  title     = {In-situ Investigation of Surface Relief Grating Formation in Photosensitive Polymers},
  year      = {2004},
  language  = {en}
}
@article{PietschSaphiannikovaHennebergetal.2004,
  author    = {Pietsch, Ullrich and Saphiannikova, Marina and Henneberg, Oliver and Geue, Thomas},
  title     = {Non-linear effects during inscription of azobenzene surface relief gratings},
  year      = {2004},
  language  = {en}
}
@article{SaphiannikovaHennebergGeneetal.2004,
  author    = {Saphiannikova, Marina and Henneberg, Oliver and Gene, T. M. and Pietsch, Ullrich and Rochon, Paul},
  title     = {Nonlinear effects during inscription of azobenzene surface relief gratings},
  issn      = {1520-6106},
  year      = {2004},
  abstract  = {Surface relief gratings were inscribed on azobenzene polymer films using a pulselike exposure of an Ar+ laser. The inscription process was initiated by a sequence of short pulses followed by much longer relaxation pauses. The development of the surface relief grating was probed by a He-Ne laser measuring the scattering intensity of the first- order grating peak. The growth time of the surface relief grating was found to be larger than the length of the pulses used. This unusual behavior can be considered as a nonlinear material response associated with the trans-cis isomerization of azobenzene moieties. In this study the polymer stress was assumed to be proportional to the number of cis-isomers. One-dimensional viscoelastic analysis was used to derive the polymer deformation. The rate of trans-cis isomerization increases with the intensity of the inscribing light; in the dark it is equal to the rate of thermal cis- trans isomerization. The respective relaxation times were estimated by fitting theoretical deformation curves to experimental data},
  language  = {en}
}
@article{HennebergGeuePietschetal.2004,
  author    = {Henneberg, Oliver and Geue, Thomas and Pietsch, Ullrich and Winter, Bernd},
  title     = {Investigation of azobenzene side group orientation in polymer surface relief gratings by means of photoelectron spectroscopy},
  year      = {2004},
  abstract  = {The molecular orientation of azobenzene side groups in polymer films before (nonpatterned) and after (patterned) development of a surface relief grating has been investigated by photoelectron spectroscopy using synchrotron radiation. The photoemission spectra obtained for 60-100 eV photons of a patterned and a nonpatterned surface are similar when the polarization vector of the synchrotron light is parallel to the grating vector. However, for perpendicular excitation, considerable spectral intensity differences can be observed for 9-14 eV electron binding energy. The observed changes are attributed to the formation of well-oriented azobenzenes at the surface. (C) 2004 American Institute of Physics},
  language  = {en}
}
@article{StillerKarageorgievBuchsteineretal.2003,
  author    = {Stiller, Burkhard and Karageorgiev, Peter and Buchsteiner, Andrea and Geue, Thomas and Henneberg, Oliver and Brehmer, Ludwig and Natansohn, Almeria and Hollricher, Olga},
  title     = {Using light as a tool : optically Induced mass transport generated in Near-Fields},
  issn      = {0038-7355 -},
  year      = {2003},
  language  = {en}
}
@article{GeueHennebergGrenzeretal.2002,
  author    = {Geue, Thomas and Henneberg, Oliver and Grenzer, J{\"o}rg and Pietsch, Ullrich and Natansohn, Almeria and Rochon, Paul and Finkelstein, Kenneth D.},
  title     = {Formation of a buried density grating on thermal erasure of azobenzene polymer surface gratings},
  issn      = {0927-7757},
  year      = {2002},
  language  = {en}
}
@article{GeueHennebergPietsch2002,
  author    = {Geue, Thomas and Henneberg, Oliver and Pietsch, Ullrich},
  title     = {X-ray reflectivity from sinusoidal surface relief gratings},
  issn      = {0023-4753},
  year      = {2002},
  language  = {en}
}
@phdthesis{Henneberg2004,
  author    = {Henneberg, Oliver},
  title     = {In-situ Untersuchungen zur Entstehung von Oberfl{\"a}chengittern in Polymeren},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-0001331},
  school      = {Universit{\"a}t Potsdam},
  year      = {2004},
  abstract  = {In festen azobenzenhaltigen Polymeren wurde bei Bestrahlung mit blauem Licht ein makroskopischer Materialtransport beobachtet. Um die Dynamik der Gitterentstehung zu verfolgen, wurde am Speicherring f{\"u}r Synchrotronstrahlung ein Gitterschreibaufbau errichtet. Damit konnte erstmals in dieser Arbeit die Gitterbildungsgeschwindigkeit in-situ simultan mit R{\"o}ntgen- und Lichtstreuung untersucht werden. Mit Hilfe einer speziellen Anpassung der R{\"o}ntgenstreutheorie konnten sehr gute {\"U}bereinstimmungen von theoretischen Berechnungen mit den Messergebnissen erzielt werden. Dabei konnte nachgewiesen werden, dass sich zeitgleich mit einem Oberfl{\"a}chengitter auch ein Dichtegitter entwickelt. Durch die Trennung beider Streuanteile ließ sich die Dynamik der Strukturentstehungen bestimmen. Des weiteren konnte erstmals mit Hilfe der Photoelektronenspektroskopie die molekulare Orientierung an der Oberfl{\"a}che eines Oberfl{\"a}chengitters nachgewiesen werden. Die Bewegungsursache kann auf einen Impuls{\"u}bertrag w{\"a}hrend der Isomerisierung zur{\"u}ckgef{\"u}hrt werden, w{\"a}hrend die Bewegungsrichtung durch den elektrischen Feldvektor festgelegt wird. Die Theorie der Gitterentstehung konnte verbessert werden.},
  language  = {de}
}
@article{HennebergPietschPanzneretal.2006,
  author    = {Henneberg, Oliver and Pietsch, Ullrich and Panzner, Tobias and Geue, Thomas and Finkelstein, Kenneth D.},
  title     = {Simultaneous X-ray and visible light diffraction for the investigation of surface relief and density grating formation in azobenzene containing polymer films},
  issn      = {1542-1406},
  doi       = {10.1080/15421400500383345},
  year      = {2006},
  abstract  = {The development of surface relief and density patterns in azobenzene polymer films was studied by diffraction at two different wavelengths. We used x-ray diffraction of synchrotron radiation at 0.124 nm in combination with visible light diffraction at a wavelength of 633 nm. In contrast to visible light scattering x-ray diffraction allows the separation of a surface relief and a density grating contribution due to the different functional dependence of the scattering power. Additionally, the x-ray probe is most sensitive for the onset of the surface grating formation},
  language  = {en}
}
@article{HennebergGeueSaphiannikovaetal.2001,
  author    = {Henneberg, Oliver and Geue, Thomas and Saphiannikova, Marina and Pietsch, Ullrich and Rochon, Paul and Natansohn, Almeria},
  title     = {Formation and dynamics of polymer surface relief gratings},
  issn      = {0378-5963},
  year      = {2001},
  language  = {en}
}