@misc{JelkenSanter2019,
  author    = {Jelken, Joachim and Santer, Svetlana},
  title     = {Light induced reversible structuring of photosensitive polymer films},
  series = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  journal   = {Postprints der Universit{\"a}t Potsdam Mathematisch-Naturwissenschaftliche Reihe},
  number    = {750},
  issn      = {1866-8372},
  doi       = {10.25932/publishup-43643},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-436432},
  pages     = {20295 -- 20305},
  year      = {2019},
  abstract  = {In this paper we report on photoswitchable polymer surfaces with dynamically and reversibly fluctuating topographies. It is well known that when azobenzene containing polymer films are irradiated with optical interference patterns the film topography changes to form a surface relief grating. In the simplest case, the film shape mimics the intensity distribution and deforms into a wave like, sinusoidal manner with amplitude that may be as large as the film thickness. This process takes place in the glassy state without photo-induced softening. Here we report on an intriguing discovery regarding the formation of reliefs under special illumination conditions. We have developed a novel setup combining the optical part for creating interference patterns, an AFM for in situ acquisition of topography changes and diffraction efficiency signal measurements. In this way we demonstrate that these gratings can be "set in motion" like water waves or dunes in the desert. We achieve this by applying repetitive polarization changes to the incoming interference pattern. Such light responsive surfaces represent the prerequisite for providing practical applications ranging from conveyer or transport systems for adsorbed liquid objects and colloidal particles to generation of adaptive and dynamic optical devices.},
  language  = {en}
}
@misc{DiFlorioBruendermannYadavallietal.2013,
  author    = {Di Florio, Giuseppe and Br{\"u}ndermann, Erik and Yadavalli, Nataraja Sekhar and Santer, Svetlana and Havenith, Martina},
  title     = {Polarized 3D Raman and nanoscale near-field optical microscopy of optically inscribed surface relief gratings},
  url       = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-95233},
  pages     = {1544 -- 1554},
  year      = {2013},
  abstract  = {We have used polarized confocal Raman microspectroscopy and scanning near-field optical microscopy with a resolution of 60 nm to characterize photoinscribed grating structures of azobenzene doped polymer films on a glass support. Polarized Raman microscopy allowed determining the reorientation of the chromophores as a function of the grating phase and penetration depth of the inscribing laser in three dimensions. We found periodic patterns, which are not restricted to the surface alone, but appear also well below the surface in the bulk of the material. Near-field optical microscopy with nanoscale resolution revealed lateral two-dimensional optical contrast, which is not observable by atomic force and Raman microscopy.},
  language  = {en}
}